Supplier part form (#11884)

* Fix SupplierPart sub-form

Co-authored-by: Copilot <copilot@github.com>

* Fix details panel for SupplierPart page

---------

Co-authored-by: Copilot <copilot@github.com>

src/frontend/src/forms/PurchaseOrderForms.tsx

@@ -144,10 +144,25 @@ export function usePurchaseOrderLineItemFields({
           };
         },
         addCreateFields: {
-          part: {},
+          part: {
+            filters: {
+              active: true,
+              purchaseable: true
+            }
+          },
           SKU: {},
+          manufacturer_part: {
+            filters: {
+              part_detail: true,
+              manufacturer_detail: true,
+              active: true
+            }
+          },
           description: {},
-          supplier: { hidden: true }
+          supplier: {
+            hidden: true,
+            value: supplierId
+          }
         }
       },
       line: {},

src/frontend/src/pages/company/SupplierPartDetail.tsx

@@ -79,9 +79,11 @@ export default function SupplierPartDetail() {
     const data = supplierPart ?? {};
 
     // Access nested data
-    data.manufacturer = data.manufacturer_detail?.pk;
+    data.manufacturer =
-    data.MPN = data.manufacturer_part_detail?.MPN;
+      supplierPart.manufacturer || data.manufacturer_detail?.pk;
-    data.manufacturer_part = data.manufacturer_part_detail?.pk;
+    data.MPN = supplierPart.MPN || data.manufacturer_part_detail?.MPN;
+    data.manufacturer_part =
+      supplierPart.manufacturer_part || data.manufacturer_part_detail?.pk;
 
     const tl: DetailsField[] = [
       {