feat: add PriceAdjustmentLine repository to PriceAdjustmentService and optimize pending item query

Backend/ERPCore/Services/PriceAdjustmentService.cs

@@ -25,6 +25,7 @@ public sealed class PriceAdjustmentService : IPriceAdjustmentService
     public const string ApprovalNavCode = "products.price-adjustments";
 
     private readonly IRepository<PriceAdjustment> _adjustments;
+    private readonly IRepository<PriceAdjustmentLine> _lines;
     private readonly IRepository<Item> _items;
     private readonly IRepository<ItemPriceHistory> _history;
     private readonly IRepository<User> _users;
@@ -36,11 +37,13 @@ public sealed class PriceAdjustmentService : IPriceAdjustmentService
     private readonly IUnitOfWork _uow;
 
     public PriceAdjustmentService(
-        IRepository<PriceAdjustment> adjustments, IRepository<Item> items, IRepository<ItemPriceHistory> history,
+        IRepository<PriceAdjustment> adjustments, IRepository<PriceAdjustmentLine> lines, IRepository<Item> items,
-        IRepository<User> users, IRepository<ApprovalConfig> config, IApprovalService approvals,
+        IRepository<ItemPriceHistory> history, IRepository<User> users, IRepository<ApprovalConfig> config,
-        INotificationService notifications, INumberSequenceService numbers, ICurrentUser currentUser, IUnitOfWork uow)
+        IApprovalService approvals, INotificationService notifications, INumberSequenceService numbers,
+        ICurrentUser currentUser, IUnitOfWork uow)
     {
         _adjustments = adjustments;
+        _lines = lines;
         _items = items;
         _history = history;
         _users = users;
@@ -92,10 +95,14 @@ public sealed class PriceAdjustmentService : IPriceAdjustmentService
 
         var ids = request.Lines.Select(l => l.ItemId).ToList();
         var items = await _items.Query().Where(i => ids.Contains(i.ItemId)).ToDictionaryAsync(i => i.ItemId, ct);
-        var pendingItemIds = await _adjustments.Query().AsNoTracking()
+        // Queried from the line side (not PriceAdjustment.Lines via SelectMany) so this stays a
-            .Where(p => p.Status == PriceAdjustmentStatus.PendingApproval || p.Status == PriceAdjustmentStatus.PendingSecondApproval)
+        // plain join — a SelectMany over a to-many navigation generates a CROSS APPLY that
-            .SelectMany(p => p.Lines.Select(l => new { l.ItemId, p.DocNo }))
+        // Pomelo/MySQL can't translate (it works fine against PostgreSQL, which is what this
-            .Where(x => ids.Contains(x.ItemId))
+        // predates — 2026-10-16 MySQL-port regression).
+        var pendingItemIds = await _lines.Query().AsNoTracking()
+            .Where(l => ids.Contains(l.ItemId)
+                && (l.PriceAdjustment!.Status == PriceAdjustmentStatus.PendingApproval || l.PriceAdjustment!.Status == PriceAdjustmentStatus.PendingSecondApproval))
+            .Select(l => new { l.ItemId, DocNo = l.PriceAdjustment!.DocNo })
             .ToListAsync(ct);
 
         var lines = new List<PriceAdjustmentLine>();