Refactor production and stock tests to remove UOM dependency

- Updated production.spec.ts, stock-adjustments.spec.ts, and stock-transfers.spec.ts to eliminate UOM references in API seeder and test cases.
- Adjusted ApiSeeder methods to remove UOM parameters from stock receiving and production template creation.
- Revised documentation to reflect changes in UOM handling, emphasizing that stock is counted in base UOM only.
- Introduced new enums for MeasureUnit and StageQtyUnit to clarify content size and stage input quantities.
- Implemented ItemContent service to validate and normalize content sizes.
- Updated smoke tests to validate production stage inputs expressed in content units, ensuring correct consumption calculations.
- Modified frontend UOM label handling to reflect the removal of per-line UOMs in document lines.

docs/10-BACKEND-PHASE1.md

@@ -119,8 +119,8 @@ One base currency; invoicing/3-way match in Accounting (GRN carries data); users
 | ID | Requirement | Pri |
 |---|---|---|
 | FR-MD-01 | Maintain **Item master**: SKU (unique), name, description, category (+ optional subcategory), optional brand, **stock nature** (Stocked/NonStocked/Service), tracking mode (None/Batch/Serial), status, tax class, default vendor, **optional fixed sale price** (nullable; Sales-only — never enters costing/GRN/FIFO; `null` ⇒ item is sold at its stock/FIFO value). | M |
-| FR-MD-02 | Maintain **UOM master** with base UOM per item and **conversion factors** (purchase→stock→base). | M |
-| FR-MD-03 | Convert quantities between UOMs on every transaction; store base-UOM quantity in the ledger. | M |
+| FR-MD-02 | Maintain **UOM master**, with one base UOM per item — the pack it is stocked and counted in. An item may also carry an optional **content size** (how much one pack holds: 500 ml, 50 kg), entered in ml/L/g/kg and stored normalised to ml or g. *(Revised 2026-08-11: per-item conversion factors are gone — see the note below.)* | M |
+| FR-MD-03 | Record every transaction quantity as a count of the item's base UOM. There is **no conversion**: a differently sized pack is a different item. The one exception is a production stage input, which may be written in the item's content unit and is divided by the content size to get the pack count (FR-MFG-04). | M |
 | FR-MD-04 | Maintain **item categories with one optional subcategory level**. An item references a category (required) and a subcategory (optional) that must belong to it. Deeper nesting is not supported. | S |
 | FR-MD-05 | Hold **reorder point** and **reorder quantity** per item, optionally per warehouse. | M |
 | FR-MD-06 | Maintain **Vendor master**: code, name, contact, terms, tax reg, status, currency. | M |
@@ -266,9 +266,10 @@ SUBCATEGORY(subcategory_id PK, category_id FK→CATEGORY, name, status)
 BRAND(brand_id PK, name, status)
 ITEM_TYPE(item_type_id PK, name, status)                  -- Color, Size, Material — standalone
 UOM(uom_id PK, name)
-UOM_CONVERSION(conversion_id PK, item_id FK→ITEM, from_uom FK→UOM, to_uom FK→UOM, factor)
 ITEM(item_id PK, sku, name, category_id FK→CATEGORY, subcategory_id FK→SUBCATEGORY [nullable],
      brand_id FK→BRAND [nullable], base_uom_id FK→UOM,
+     content_qty [nullable], content_unit [nullable],        -- as entered (Ml|L|G|Kg)
+     content_base_qty [nullable], content_base_unit [nullable],  -- normalised, Ml|G only
      default_vendor_id FK→VENDOR, stock_nature, tracking_mode, tax_class,
      sale_price [nullable], status)   -- sale_price: Sales-only selling price; NULL ⇒ sell at stock (FIFO) value
 ITEM_REORDER(reorder_id PK, item_id FK→ITEM, warehouse_id FK→WAREHOUSE, reorder_point, reorder_qty)