fix(models): remove timestamps from models where tables lack createdAt/updatedAt columns

Add withDateSessionMixin for proper timestamp handling and fix models
to return empty timestamps array when database tables don't have
created_at/updated_at columns. This prevents ORM insert/update errors.

Models updated:
- Branch, Role, RolePermission, ViewColumn, ViewRole
- InventoryAdjustment, InventoryAdjustmentEntry, InventoryTransactionMeta
- BillLandedCostEntry, CreditNote, CreditNoteAppliedInvoice, RefundCreditNote
- PaymentReceived, SaleInvoice, SaleReceipt, Item, ItemEntry
- RefundVendorCredit, VendorCreditAppliedBill
- ItemWarehouseQuantity, Warehouse, WarehouseTransfer, WarehouseTransferEntry
- Setting, TenantMetadataModel, TenantUser

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

packages/server/src/modules/Items/models/Item.ts

@@ -44,6 +44,13 @@ export class Item extends TenantBaseModel {
     return 'items';
   }
 
+  /**
+   * Timestamps columns.
+   */
+  get timestamps() {
+    return ['createdAt', 'updatedAt'];
+  }
+
   /**
    * Model modifiers.
    */