revert: restore production to the state before 730d0bd (PM/RBAC work moved to 'pm')

Their three commits (730d0bd, 5a9b543, 387edfb) reached production by push and
auto-deployed. 387edfb expects a users.username column that the live database does
not have, so POST /api/v1/auth/login was returning HTTP 500. Their schema changes
never applied either (projects still has only id, name, description, start_date,
pm_user_id, created_at), so nothing depends on the reverted code.

This commit sets the tree back to exactly a02b3ea — verified with git diff against
it — while keeping history linear: the work itself is preserved on 'pm' at 387edfb.

frontend/src/pages/Inventory/ChangeInventoryPage.tsx

@@ -76,9 +76,8 @@ export function ChangeInventoryPage() {
     }
   }, [params]);
 
-  const isAdmin = user?.role === "admin";
-  const isSupervisor = user?.role === "supervisor";
-  const canModify = isSupervisor || isAdmin;
+  const isAdmin = user?.role === "admin" || user?.role === "procurement_manager";
+  const isPM = user?.role === "pm";
 
   const warehouses = data.warehouses;
   const whOpts = useMemo(
@@ -402,7 +401,7 @@ export function ChangeInventoryPage() {
 
   const meta = FORM_TYPES.find((f) => f.t === type)!;
 
-  if (!canModify) {
+  if (isAdmin) {
     return (
       <div className="min-h-screen">
         <Header title="تغییر موجودی" backTo="/inventory" backLabel="بازگشت به داشبورد" />
@@ -410,12 +409,22 @@ export function ChangeInventoryPage() {
           <div className="rounded-xl border border-line bg-panel p-8 text-center">
             <div className="text-3xl">🔒</div>
             <h3 className="mt-2 text-[15px] font-bold">دسترسی فقط‌خواندنی</h3>
-            <p className="mt-1 text-[12.5px] text-muted">امکان تغییر موجودی انبار منحصراً در اختیار سرپرست پروژه و ادمین است.</p>
+            <p className="mt-1 text-[12.5px] text-muted">نقش ادمین اجازه ثبت تغییر موجودی ندارد. این بخش برای مدیران پروژه فعال است.</p>
           </div>
         </PageLayout>
       </div>
     );
   }
+  if (!isPM) {
+    return (
+      <div className="min-h-screen">
+        <Header title="تغییر موجودی" backTo="/inventory" backLabel="بازگشت به داشبورد" />
+        <PageLayout>
+          <div className="text-[13px] text-muted">این بخش فقط برای مدیر پروژه است.</div>
+        </PageLayout>
+      </div>
+    );
+  }
 
   const isCount = type === "STOCK_COUNT";
   const isTransfer = type === "TRANSFER";