feat(frontend): unified warehouse UI, calendar fix, partial receipts, RBAC views, admin panel, dev-mode 3-step

- header: icon box + dynamic subheader '[user] | [role] – [project/همه پروژهها]'
  on every warehouse page; module context kept in the hamburger (items 1-2)
- project manager view: office button + inline logout removed; hamburger
  contains only «خروج از حساب»; sub-views get «بازگشت به داشبورد» (Header
  backTo/goBack); «افزایش موجود» primary button on the dashboard (item 8)
- daily control: cells render the day-of-month (was the Jalali year),
  month nav uses real Jalali months, header is pure Jalali
  «امروز ۸ شهریور ۱۴۰۵», today gets a blue accent (item 3)
- arrivals: partial (item/qty) receipt — any valid item is enough to submit,
  ceiling + allocation-sum validation with inline errors, Received/In-Transit
  badges; ledger shows «رسیده X از Y» / «در راه Z» + «رسید جزیی» badge (item 4)
- api client: multipart uploads no longer send Content-Type json (fixes the
  invoice/proforma 400 «دادهی ارسالشده نامعتبر است»); undefined query
  params are dropped (fixes empty admin project filter, item 5)
- organization: user-creation card removed, role column read-only for
  procurement manager, Casdoor sync button (item 6)
- admin panel (/admin): Casdoor user sync + grant/revoke «مدیر تدارکات»;
  Developer Mode is a 3-step admin-gated flow on the login page (item 7)

frontend/src/App.tsx

@@ -38,6 +38,9 @@ const WarehousesPage = lazy(() =>
 const OrganizationPage = lazy(() =>
   import("./pages/Inventory/OrganizationPage").then((m) => ({ default: m.OrganizationPage })),
 );
+const AdminPanelPage = lazy(() =>
+  import("./pages/Admin/AdminPanel").then((m) => ({ default: m.AdminPanel })),
+);
 
 function Loading() {
   return (
@@ -178,6 +181,14 @@ export default function App() {
             </RequireAuth>
           }
         />
+        <Route
+          path="/admin"
+          element={
+            <RequireAuth>
+              <AdminPanelPage />
+            </RequireAuth>
+          }
+        />
         <Route path="*" element={<Navigate to="/" replace />} />
       </Routes>
     </Suspense>