feat: add production templates API and documentation for manufacturing phase 2

- Implemented CRUD operations for production templates, including listing, retrieving, creating, updating, and deactivating templates.
- Introduced a new API contract for production runs, detailing the lifecycle from creation to completion, including handling of stock inputs and outputs.
- Documented the architecture, requirements, entity model, and API contract for the manufacturing phase 2, ensuring clarity on the production process and its integration with existing systems.

Backend/ERPCore/Domain/DocumentTypes.cs

@@ -14,4 +14,7 @@ public static class DocumentTypes
     public const string Adjustment = "ADJ";
     public const string Count = "CNT";
     public const string PurchaseReturn = "PRET";
+
+    /// <summary>Production run (docs/30 FR-MFG-08) — <c>PRD-2026-00001</c>.</summary>
+    public const string Production = "PRD";
 }

Backend/ERPCore/Domain/Entities/ProductionRun.cs

@@ -0,0 +1,59 @@
+using ERPCore.Domain.Enums;
+
+namespace ERPCore.Domain.Entities;
+
+/// <summary>
+/// One execution instance of a template (FR-MFG-08), numbered <c>PRD-2026-00001</c>.
+/// Every stage, input, output and edge is <b>copied</b> from the template at creation
+/// with quantities scaled by <see cref="ScaleFactor"/>, so a completed run stays
+/// readable even if the template is later edited (FR-MFG-06).
+/// <para>The run's <b>cost pool</b> is derived, never stored:
+/// <c>Σ RunStageInput.ConsumedValue − Σ RunStageInput.ReturnedValue</c>. The terminal
+/// approve divides it by the good quantity to cost the finished layer, then closes it
+/// (FR-MFG-13, <c>409 RUN_COST_CLOSED</c>).</para>
+/// Mutable aggregate with a <see cref="RowVersion"/> token. Model: docs/30 Part C.
+/// </summary>
+public class ProductionRun
+{
+    public int RunId { get; set; }
+    public string DocNo { get; set; } = string.Empty;
+
+    public int TemplateId { get; set; }
+    public ProductionTemplate? Template { get; set; }
+
+    /// <summary>Stock inputs are consumed from, and the finished good received into, this warehouse.</summary>
+    public int WarehouseId { get; set; }
+    public Warehouse? Warehouse { get; set; }
+
+    /// <summary>Optional destination bin for the finished goods. Reaches the ledger only — stock layers carry no bin.</summary>
+    public int? OutputBinId { get; set; }
+    public Bin? OutputBin { get; set; }
+
+    /// <summary>Target quantity of the finished item; drives <see cref="ScaleFactor"/>.</summary>
+    public decimal TargetQty { get; set; }
+
+    /// <summary><c>TargetQty / terminalOutput.QtyPerBatch</c>, applied to every copied quantity.</summary>
+    public decimal ScaleFactor { get; set; }
+
+    public ProductionRunStatus Status { get; set; } = ProductionRunStatus.InProgress;
+
+    /// <summary>Incremented by each terminal reject (FR-MFG-16); prior figures live in the event history.</summary>
+    public int ReworkCount { get; set; }
+
+    public int? CancelReasonCodeId { get; set; }
+    public ReasonCode? CancelReason { get; set; }
+
+    public int CreatedBy { get; set; }
+    public User? Creator { get; set; }
+
+    public DateTime CreatedAt { get; set; }
+
+    /// <summary>Set by the terminal approve only. A cancelled run leaves this null.</summary>
+    public DateTime? CompletedAt { get; set; }
+
+    public uint RowVersion { get; set; }
+
+    public ICollection<RunStage> Stages { get; set; } = new List<RunStage>();
+    public ICollection<RunEdge> Edges { get; set; } = new List<RunEdge>();
+    public ICollection<RunStageEvent> Events { get; set; } = new List<RunStageEvent>();
+}

Backend/ERPCore/Domain/Entities/ProductionTemplate.cs

@@ -0,0 +1,43 @@
+using ERPCore.Domain.Enums;
+
+namespace ERPCore.Domain.Entities;
+
+/// <summary>
+/// A reusable production-line definition — the stage graph designed on the canvas
+/// (FR-MFG-01). Never hard-deleted once referenced by a run; deactivated instead
+/// (FR-MD-08 posture). Editing is locked while any run of it is InProgress
+/// (FR-MFG-06, <c>409 TEMPLATE_IN_USE</c>) — edit-lock replaces versioning, which is
+/// why runs copy display fields at creation. Mutable aggregate with a
+/// <see cref="RowVersion"/> token. Model: docs/30 Part C.
+/// </summary>
+public class ProductionTemplate
+{
+    public int TemplateId { get; set; }
+    public string Code { get; set; } = string.Empty;
+    public string Name { get; set; } = string.Empty;
+    public string? Description { get; set; }
+
+    public EntityStatus Status { get; set; } = EntityStatus.Active;
+
+    /// <summary>
+    /// Canvas-only annotations (grouping boxes and divider lines) as a jsonb array, stored
+    /// verbatim and never interpreted server-side.
+    /// </summary>
+    /// <remarks>
+    /// Not in docs/30 Part C — added because the builder canvas already draws these and
+    /// without somewhere to keep them a save would silently discard the user's layout notes.
+    /// They carry no graph semantics: no ports, no edges, and the validator never sees them.
+    /// Nullable so a template that has none stores nothing rather than an empty array.
+    /// </remarks>
+    public string? Annotations { get; set; }
+
+    public int CreatedBy { get; set; }
+    public User? Creator { get; set; }
+
+    public DateTime CreatedAt { get; set; }
+    public uint RowVersion { get; set; }
+
+    public ICollection<TemplateStage> Stages { get; set; } = new List<TemplateStage>();
+    public ICollection<StageEdge> Edges { get; set; } = new List<StageEdge>();
+    public ICollection<ProductionRun> Runs { get; set; } = new List<ProductionRun>();
+}

Backend/ERPCore/Domain/Entities/RunEdge.cs

@@ -0,0 +1,28 @@
+namespace ERPCore.Domain.Entities;
+
+/// <summary>
+/// A parent → child arrow copied from the template's <see cref="StageEdge"/> set at run
+/// creation.
+/// <para><b>Addition to docs/30 Part C (recorded).</b> The doc's entity model has no run
+/// edge table, but the run graph needs its own copy: deriving edges at read time through
+/// <c>RunStage.TemplateStageId → STAGE_EDGE</c> would let a later template edit silently
+/// rewrite completed-run history — the exact thing FR-MFG-06 exists to prevent — and
+/// breaks outright once that link is nulled by a stage deletion.</para>
+/// <para>Used for the run canvas, child-readiness evaluation and reject-intake's
+/// "delivering parents". Note that <b>WIP delivery is routed by
+/// <c>RunStageInput.FromRunOutputId</c>, not by these edges</b> — an edge is display and
+/// validation only.</para>
+/// </summary>
+public class RunEdge
+{
+    public int RunEdgeId { get; set; }
+
+    public int RunId { get; set; }
+    public ProductionRun? Run { get; set; }
+
+    public int ParentRunStageId { get; set; }
+    public RunStage? ParentRunStage { get; set; }
+
+    public int ChildRunStageId { get; set; }
+    public RunStage? ChildRunStage { get; set; }
+}

Backend/ERPCore/Domain/Entities/RunStage.cs

@@ -0,0 +1,59 @@
+using ERPCore.Domain.Enums;
+
+namespace ERPCore.Domain.Entities;
+
+/// <summary>
+/// One stage of a run — a copy of a <see cref="TemplateStage"/> taken at run creation
+/// (FR-MFG-06), carrying its own live status and actual timings. Model: docs/30 Part C.
+/// <para><b>Whether this stage is terminal is derived</b>, never stored: a stage is
+/// terminal when it has no outbound <see cref="RunEdge"/>. Storing it would let it
+/// drift from the edge set.</para>
+/// </summary>
+public class RunStage
+{
+    public int RunStageId { get; set; }
+
+    public int RunId { get; set; }
+    public ProductionRun? Run { get; set; }
+
+    /// <summary>
+    /// Provenance link back to the template stage. <b>Nullable</b>: a template PUT may
+    /// delete a stage while completed/cancelled runs still reference it (the edit-lock
+    /// only blocks edits during InProgress runs), so the FK is <c>SET NULL</c> rather
+    /// than blocking the edit forever. Everything needed to display a historical run is
+    /// copied below, which is exactly what FR-MFG-06 anticipates.
+    /// </summary>
+    public int? TemplateStageId { get; set; }
+    public TemplateStage? TemplateStage { get; set; }
+
+    // --- copied from the template at run creation (FR-MFG-06) ---
+    public string Name { get; set; } = string.Empty;
+    public string? RoleLabel { get; set; }
+    public int EstimatedMinutes { get; set; }
+    public decimal PosX { get; set; }
+    public decimal PosY { get; set; }
+
+    public ProductionStageStatus Status { get; set; } = ProductionStageStatus.Waiting;
+
+    /// <summary>Stamped at start; preserved across a reject-intake rework so the original start stands (FR-MFG-19).</summary>
+    public DateTime? ActualStartAt { get; set; }
+    public DateTime? ActualEndAt { get; set; }
+
+    /// <summary>Copied from the template stage; definitions survive a rework.</summary>
+    public string FieldDefs { get; set; } = "[]";
+
+    /// <summary>Captured at complete as a jsonb object; cleared by a terminal reject so required fields are re-answered.</summary>
+    public string? FieldValues { get; set; }
+
+    /// <summary>
+    /// Concurrency token. Stage actions re-read the stage inside their transaction and
+    /// let this xmin check serialize concurrent requests — it is what stops two
+    /// simultaneous terminal approves from both reading <c>Done</c> and posting two
+    /// receipts. See the idempotency note in <c>ProductionRunService</c>.
+    /// </summary>
+    public uint RowVersion { get; set; }
+
+    public ICollection<RunStageInput> Inputs { get; set; } = new List<RunStageInput>();
+    public ICollection<RunStageOutput> Outputs { get; set; } = new List<RunStageOutput>();
+    public ICollection<RunStageEvent> Events { get; set; } = new List<RunStageEvent>();
+}

Backend/ERPCore/Domain/Entities/RunStageEvent.cs

@@ -0,0 +1,40 @@
+using ERPCore.Domain.Enums;
+
+namespace ERPCore.Domain.Entities;
+
+/// <summary>
+/// Immutable history of everything that happened to a run (docs/30 Part C). Written by
+/// every mutating action and never updated or deleted, so a run's story — including the
+/// figures discarded by each rework — survives in full.
+/// <para><b>Addition to docs/30 Part C (recorded):</b> <see cref="RunId"/>. The doc hangs
+/// events off the stage only, which leaves run-level events (cancel, terminal reject)
+/// with no home and forces the detail timeline to join through stages. Keeping both
+/// links makes <see cref="RunStageId"/> optional and the timeline a single query.</para>
+/// </summary>
+public class RunStageEvent
+{
+    public int EventId { get; set; }
+
+    public int RunId { get; set; }
+    public ProductionRun? Run { get; set; }
+
+    /// <summary>Null for run-level events (Cancel).</summary>
+    public int? RunStageId { get; set; }
+    public RunStage? RunStage { get; set; }
+
+    public RunStageEventType EventType { get; set; }
+
+    public string? Note { get; set; }
+
+    /// <summary>
+    /// Event-specific detail as jsonb — consumed layers on a Start, pulled-back
+    /// quantities on a RejectIntake, the full pre-rework snapshot on a TerminalReject.
+    /// Pre-serialized string, written only through <c>ProductionJson</c>.
+    /// </summary>
+    public string? Payload { get; set; }
+
+    public int UserId { get; set; }
+    public User? User { get; set; }
+
+    public DateTime CreatedAt { get; set; }
+}

Backend/ERPCore/Domain/Entities/RunStageInput.cs

@@ -0,0 +1,55 @@
+using ERPCore.Domain.Enums;
+
+namespace ERPCore.Domain.Entities;
+
+/// <summary>
+/// One input line of a run stage — a copy of a <see cref="StageInput"/> with its
+/// quantity scaled at creation, plus the live consumption/delivery figures.
+/// Model: docs/30 Part C.
+/// <para><b>Stock inputs</b> accumulate <see cref="ConsumedQty"/>/<see cref="ConsumedValue"/>
+/// at each start and <see cref="ReturnedQty"/>/<see cref="ReturnedValue"/> on leftover
+/// return or run cancel. Those four columns are the whole cost pool
+/// (<c>Σ consumed − Σ returned</c>) and are deliberately <b>not</b> reset by a terminal
+/// reject — already-consumed material stays in the pool (FR-MFG-16).</para>
+/// <para><b>Upstream inputs</b> accumulate <see cref="DeliveredQty"/> as parent stages
+/// transfer WIP in. The stage becomes Ready only when every upstream input has
+/// <c>DeliveredQty &gt;= PlannedQty</c> (FR-MFG-09, an all-parents join).</para>
+/// </summary>
+public class RunStageInput
+{
+    public int RunInputId { get; set; }
+
+    public int RunStageId { get; set; }
+    public RunStage? RunStage { get; set; }
+
+    public StageInputSource Source { get; set; }
+
+    public int? ItemId { get; set; }
+    public Item? Item { get; set; }
+
+    /// <summary>The parent output feeding this input. This — not <see cref="RunEdge"/> — is what routes a transfer.</summary>
+    public int? FromRunOutputId { get; set; }
+    public RunStageOutput? FromRunOutput { get; set; }
+
+    public int UomId { get; set; }
+    public Uom? Uom { get; set; }
+
+    /// <summary>Scaled at creation; per-run editable until the stage starts (FR-MFG-08, <c>409 STAGE_NOT_EDITABLE</c>).</summary>
+    public decimal PlannedQty { get; set; }
+
+    /// <summary>
+    /// Stock inputs only, in the item's <b>base</b> UOM. A start consumes
+    /// <c>max(0, PlannedQty − ConsumedQty)</c> and adds to these, so a rework restart
+    /// with an unchanged planned quantity consumes nothing and one with a raised planned
+    /// quantity consumes only the delta (FR-MFG-16).
+    /// </summary>
+    public decimal ConsumedQty { get; set; }
+    public decimal ConsumedValue { get; set; }
+
+    /// <summary>Upstream inputs only: accumulated by parent transfers.</summary>
+    public decimal DeliveredQty { get; set; }
+
+    /// <summary>Leftover returns (FR-MFG-14) and cancel returns (FR-MFG-17), at the consumed weighted cost.</summary>
+    public decimal ReturnedQty { get; set; }
+    public decimal ReturnedValue { get; set; }
+}

Backend/ERPCore/Domain/Entities/RunStageOutput.cs

@@ -0,0 +1,43 @@
+namespace ERPCore.Domain.Entities;
+
+/// <summary>
+/// One output line of a run stage — a copy of a <see cref="StageOutput"/> with its
+/// quantity scaled at creation, plus the live produced/scrapped/transferred figures.
+/// Model: docs/30 Part C.
+/// <para><b>Available to transfer is derived, never stored:</b>
+/// <c>ProducedQty − ScrappedQty − TransferredQty</c>. Every transfer path checks it and
+/// raises <c>422 TRANSFER_EXCEEDS_AVAILABLE</c> (FR-MFG-12).</para>
+/// <para>Scrap cost is <b>absorbed</b> into the run cost pool as normal yield loss — no
+/// write-off ledger entry is posted (FR-MFG-11).</para>
+/// </summary>
+public class RunStageOutput
+{
+    public int RunOutputId { get; set; }
+
+    public int RunStageId { get; set; }
+    public RunStage? RunStage { get; set; }
+
+    /// <summary>Null on intermediate (WIP) outputs; set on the terminal output — the finished good.</summary>
+    public int? ItemId { get; set; }
+    public Item? Item { get; set; }
+
+    public string Name { get; set; } = string.Empty;
+
+    public int UomId { get; set; }
+    public Uom? Uom { get; set; }
+
+    /// <summary>Scaled at creation; per-run editable until the stage starts.</summary>
+    public decimal PlannedQty { get; set; }
+
+    /// <summary>Recorded at complete. A re-complete after a rework <b>overwrites</b> this, never adds to it.</summary>
+    public decimal ProducedQty { get; set; }
+
+    public decimal ScrappedQty { get; set; }
+
+    /// <summary>Mandatory when <see cref="ScrappedQty"/> &gt; 0, context <c>Production</c> (FR-MFG-11).</summary>
+    public int? ScrapReasonCodeId { get; set; }
+    public ReasonCode? ScrapReason { get; set; }
+
+    /// <summary>Total WIP handed to children so far, across approve and any later partial transfers.</summary>
+    public decimal TransferredQty { get; set; }
+}

Backend/ERPCore/Domain/Entities/StageEdge.cs

@@ -0,0 +1,21 @@
+namespace ERPCore.Domain.Entities;
+
+/// <summary>
+/// A parent → child arrow on the template canvas. The edge set must form a DAG with
+/// at least one entry stage and exactly one terminal stage; that is enforced in
+/// <c>ProductionGraphValidator</c> on every save, not by the database (FR-MFG-02).
+/// Model: docs/30 Part C.
+/// </summary>
+public class StageEdge
+{
+    public int EdgeId { get; set; }
+
+    public int TemplateId { get; set; }
+    public ProductionTemplate? Template { get; set; }
+
+    public int ParentStageId { get; set; }
+    public TemplateStage? ParentStage { get; set; }
+
+    public int ChildStageId { get; set; }
+    public TemplateStage? ChildStage { get; set; }
+}

Backend/ERPCore/Domain/Entities/StageInput.cs

@@ -0,0 +1,39 @@
+using ERPCore.Domain.Enums;
+
+namespace ERPCore.Domain.Entities;
+
+/// <summary>
+/// One line of a stage's input formula (FR-MFG-04). Exactly one of the two source
+/// shapes applies, enforced by <c>ProductionGraphValidator</c>:
+/// <list type="bullet">
+/// <item><see cref="StageInputSource.Stock"/> — <see cref="ItemId"/> set,
+/// <see cref="FromOutputId"/> null. FIFO-consumed from the run warehouse at stage
+/// start. Allowed on <i>any</i> stage, e.g. packaging added late.</item>
+/// <item><see cref="StageInputSource.Upstream"/> — <see cref="FromOutputId"/> set to
+/// an output of a <b>direct parent</b> stage, <see cref="ItemId"/> null. Flows as
+/// internal WIP and never touches stock or the ledger.</item>
+/// </list>
+/// Model: docs/30 Part C.
+/// </summary>
+public class StageInput
+{
+    public int InputId { get; set; }
+
+    public int StageId { get; set; }
+    public TemplateStage? Stage { get; set; }
+
+    public StageInputSource Source { get; set; }
+
+    /// <summary>Required when <see cref="Source"/> is Stock; null when Upstream.</summary>
+    public int? ItemId { get; set; }
+    public Item? Item { get; set; }
+
+    /// <summary>Required when <see cref="Source"/> is Upstream; must belong to a direct parent.</summary>
+    public int? FromOutputId { get; set; }
+    public StageOutput? FromOutput { get; set; }
+
+    public int UomId { get; set; }
+    public Uom? Uom { get; set; }
+
+    public decimal QtyPerBatch { get; set; }
+}

Backend/ERPCore/Domain/Entities/StageOutput.cs

@@ -0,0 +1,27 @@
+namespace ERPCore.Domain.Entities;
+
+/// <summary>
+/// A named quantity produced by a stage (FR-MFG-05). Intermediate outputs are
+/// <b>internal WIP only</b> — <see cref="ItemId"/> is null, no stock and no ledger row
+/// is ever written for them. The terminal stage is the exception: it has exactly one
+/// output and that output <b>must</b> reference a real Item (the finished good), which
+/// is what the production receipt creates a layer for. Model: docs/30 Part C.
+/// </summary>
+public class StageOutput
+{
+    public int OutputId { get; set; }
+
+    public int StageId { get; set; }
+    public TemplateStage? Stage { get; set; }
+
+    /// <summary>Null on intermediate stages; required on the terminal stage.</summary>
+    public int? ItemId { get; set; }
+    public Item? Item { get; set; }
+
+    public string Name { get; set; } = string.Empty;
+
+    public int UomId { get; set; }
+    public Uom? Uom { get; set; }
+
+    public decimal QtyPerBatch { get; set; }
+}

Backend/ERPCore/Domain/Entities/TemplateStage.cs

@@ -0,0 +1,36 @@
+namespace ERPCore.Domain.Entities;
+
+/// <summary>
+/// One box on the template canvas (FR-MFG-03): a named step with a role label, an
+/// estimated duration, a formula (<see cref="Inputs"/> + <see cref="Outputs"/>) and
+/// custom field definitions. Model: docs/30 Part C.
+/// </summary>
+public class TemplateStage
+{
+    public int StageId { get; set; }
+
+    public int TemplateId { get; set; }
+    public ProductionTemplate? Template { get; set; }
+
+    public string Name { get; set; } = string.Empty;
+
+    /// <summary>Free text (e.g. "QA"). Informational only this phase — never enforced (FR-X-01).</summary>
+    public string? RoleLabel { get; set; }
+
+    public int EstimatedMinutes { get; set; }
+
+    /// <summary>Canvas coordinates — stored verbatim, never interpreted server-side (FR-MFG-03).</summary>
+    public decimal PosX { get; set; }
+    public decimal PosY { get; set; }
+
+    /// <summary>
+    /// Custom field definitions as jsonb: <c>[{ key, label, type, options?, required }]</c>
+    /// (FR-MFG-07). Held as a pre-serialized string, matching the <c>AuditLog.ChangeSet</c>
+    /// precedent; always written through <c>ProductionJson</c> so the column can only ever
+    /// hold canonical JSON.
+    /// </summary>
+    public string FieldDefs { get; set; } = "[]";
+
+    public ICollection<StageInput> Inputs { get; set; } = new List<StageInput>();
+    public ICollection<StageOutput> Outputs { get; set; } = new List<StageOutput>();
+}

Backend/ERPCore/Domain/Enums/CustomFieldType.cs

@@ -0,0 +1,16 @@
+namespace ERPCore.Domain.Enums;
+
+/// <summary>
+/// Input type of a stage custom field (FR-MFG-07; docs/30 §D.5 <c>fieldType</c>).
+/// Lives inside the <c>field_defs</c> jsonb rather than a column, but is modelled as an
+/// enum so a bad value is rejected at the DTO boundary instead of reaching the database.
+/// <see cref="Select"/> is the only type that reads <c>options</c>.
+/// </summary>
+public enum CustomFieldType
+{
+    Text,
+    Number,
+    Checkbox,
+    Date,
+    Select
+}

Backend/ERPCore/Domain/Enums/ProductionRunStatus.cs

@@ -0,0 +1,14 @@
+namespace ERPCore.Domain.Enums;
+
+/// <summary>
+/// Lifecycle of a production run (docs/30 §B.4, §D.5). A run is created
+/// <see cref="InProgress"/> and reaches exactly one final state: it completes at the
+/// terminal stage's approve (production receipt, FR-MFG-13) or is cancelled with a
+/// stock return (FR-MFG-17). Stored as a string.
+/// </summary>
+public enum ProductionRunStatus
+{
+    InProgress,
+    Completed,
+    Cancelled
+}

Backend/ERPCore/Domain/Enums/ProductionStageStatus.cs

@@ -0,0 +1,22 @@
+namespace ERPCore.Domain.Enums;
+
+/// <summary>
+/// Status of one stage within a production run (docs/30 §B.4, §D.5).
+/// <code>
+/// Waiting ──(all upstream inputs fully delivered)──▶ Ready
+/// Ready ──start (FIFO-consume Stock inputs)──▶ InProgress
+/// InProgress ──complete (produced/scrap/fields)──▶ Done
+/// Done ──approve──▶ Approved   (non-terminal: WIP transfers out; terminal: receipt)
+/// </code>
+/// Rejection is not a resting state (FR-MFG-15/16): a reject immediately produces a
+/// rework transition back into this set and is recorded as a
+/// <see cref="RunStageEventType"/> instead. Stored as a string.
+/// </summary>
+public enum ProductionStageStatus
+{
+    Waiting,
+    Ready,
+    InProgress,
+    Done,
+    Approved
+}

Backend/ERPCore/Domain/Enums/ReasonContext.cs

@@ -5,5 +5,8 @@ public enum ReasonContext
 {
     Adjustment,
     Return,
-    Count
+    Count,
+
+    /// <summary>Manufacturing: scrap, leftover return, run cancel (docs/30 §A.2).</summary>
+    Production
 }

Backend/ERPCore/Domain/Enums/RunStageEventType.cs

@@ -0,0 +1,20 @@
+namespace ERPCore.Domain.Enums;
+
+/// <summary>
+/// Kind of entry in a run's immutable history (docs/30 Part C, <c>RUN_STAGE_EVENT</c>).
+/// Every mutating action on a run writes exactly one event carrying who/when plus a
+/// jsonb payload; <see cref="TerminalReject"/> additionally snapshots the whole run's
+/// figures for the rework pass being discarded (FR-MFG-16). Stored as a string.
+/// </summary>
+public enum RunStageEventType
+{
+    Start,
+    Complete,
+    Approve,
+    Transfer,
+    RejectIntake,
+    TerminalReject,
+    LeftoverReturn,
+    Cancel,
+    QuantityEdit
+}

Backend/ERPCore/Domain/Enums/StageInputSource.cs

@@ -0,0 +1,14 @@
+namespace ERPCore.Domain.Enums;
+
+/// <summary>
+/// Where a stage input's material comes from (FR-MFG-04; docs/30 §D.5).
+/// <see cref="Stock"/> inputs reference an Item and are FIFO-consumed from the run
+/// warehouse when the stage starts. <see cref="Upstream"/> inputs reference a direct
+/// parent stage's output and flow as internal WIP — they never touch the ledger.
+/// Stored as a string.
+/// </summary>
+public enum StageInputSource
+{
+    Stock,
+    Upstream
+}

Backend/ERPCore/Domain/LedgerSourceTypes.cs

@@ -0,0 +1,34 @@
+namespace ERPCore.Domain;
+
+/// <summary>
+/// Additional <c>STOCK_LEDGER.source_doc_type</c> values for manufacturing movements
+/// (docs/30 §A.2). <c>source_doc_id</c> is always the <c>run_id</c>, so
+/// <c>LIKE 'PRD%'</c> traces every stock movement a run caused.
+/// </summary>
+/// <remarks>
+/// <para><b>Deviation from docs/30 §A.2 (recorded).</b> The doc proposes the long names
+/// <c>ProductionIssue</c>/<c>ProductionReceipt</c>/<c>ProductionReturn</c>/
+/// <c>ProductionCancelReturn</c>, but both <c>stock_ledger.SourceDocType</c> and
+/// <c>journal_entry_stubs.SourceDocType</c> are <c>varchar(10)</c> and every existing
+/// value is a short prefix (<c>GRN</c>, <c>TRF</c>, <c>ADJ</c>, <c>PRET</c>). Widening
+/// those columns would be a second Phase-1 schema change beyond the single deviation
+/// §A.1 declares (NFR-08), so the short codes below extend the existing convention
+/// instead. docs/30 §A.2 and §D.5 are amended to match.</para>
+/// <para>These are <b>not</b> <see cref="DocumentTypes"/> entries — production issues no
+/// document per movement. The run's own document number uses
+/// <see cref="DocumentTypes.Production"/> (<c>PRD-2026-00001</c>).</para>
+/// </remarks>
+public static class LedgerSourceTypes
+{
+    /// <summary>Stock consumed by a stage start (FR-MFG-10). Outbound.</summary>
+    public const string ProductionIssue = "PRDI";
+
+    /// <summary>Finished goods received at the terminal approve (FR-MFG-13). Inbound.</summary>
+    public const string ProductionReceipt = "PRDR";
+
+    /// <summary>Unconsumed material returned before receipt (FR-MFG-14). Inbound.</summary>
+    public const string ProductionReturn = "PRDL";
+
+    /// <summary>Net consumed stock returned when a run is cancelled (FR-MFG-17). Inbound.</summary>
+    public const string ProductionCancelReturn = "PRDC";
+}