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.

Testing/e2e/pages/GrnPages.ts

@@ -54,15 +54,17 @@ export class GrnNewPage {
   }
 
   /**
-   * Item and UOM are each only a combobox when the row is NOT tied to a PO line
-   * (`line.poLineId` gates both cells identically in the source - a PO line renders them as
-   * plain text instead). Checked per-cell (td:nth(0) for Item, td:nth(1) for UOM) rather than
-   * "row has any combobox", since the Bin/Hold-status cells always have one regardless of PO
-   * mode - a row-wide check would false-positive on a PO line and select the wrong control.
-   * Selecting the app doesn't auto-fill UOM from the chosen item, so a direct-receipt/off-PO
-   * line needs it set explicitly or submit blocks with "Select a UOM".
+   * Item is only a combobox when the row is NOT tied to a PO line (`line.poLineId` gates the
+   * cell in the source - a PO line renders it as plain text instead). Checked per-cell
+   * (td:nth(0)) rather than "row has any combobox", since the Bin/Hold-status cells always
+   * have one regardless of PO mode - a row-wide check would false-positive on a PO line and
+   * select the wrong control.
+   *
+   * td:nth(1) is still the UOM column, but it is now a read-only label showing the chosen
+   * item's base UOM: lines carry no unit of their own, so there is nothing to pick. The
+   * column was kept rather than removed, which is why every index below is unchanged.
    */
-  async fillFirstLine(opts: { item?: string; uom?: string; qty: number; unitCost?: number }) {
+  async fillFirstLine(opts: { item?: string; qty: number; unitCost?: number }) {
     const row = this.firstRow()
     const cells = row.locator("td")
     if (opts.item) {
@@ -71,12 +73,6 @@ export class GrnNewPage {
         await selectOption(this.page, itemCombo, opts.item)
       }
     }
-    if (opts.uom) {
-      const uomCombo = cells.nth(1).getByRole("combobox")
-      if (await uomCombo.count()) {
-        await selectOption(this.page, uomCombo, opts.uom)
-      }
-    }
     const numberInputs = row.locator('input[type="number"]')
     await numberInputs.nth(0).fill(String(opts.qty)) // Qty
     if (opts.unitCost !== undefined) {