fix: 2026-06-09 full-codebase audit hardening

Validation: shared NaN-guarded Zod coercion helpers in schemas/common.ts replace
the raw number|string transform idiom across every schema (the root-cause NaN bug
class); emailOrEmpty + lenient isoDateString/timeString.

Security: roles privilege-escalation closed; refresh-token family revocation on
reuse; TOTP uses config params; read endpoints permission-guarded; received-invoices
gross VAT on all paths; orders-pdf custom-items authz.

Concurrency: $queryRaw SELECT...FOR UPDATE locks in ascending-id order (warehouse
confirm/cancel, attendance lockUserRow); uniqueness checks moved into create
transactions (TOCTOU -> 409); deterministic id tiebreak on second-precision
timestamp ordering (plan resolveCell/resolveGrid, warehouse FIFO).

Frontend: Rules-of-Hooks fixed across ~14 pages + PlanCellModal; UTC-date persisted
fields; dashboard invalidation gaps; stale-closure confirm bugs.

Tooling/tests: ESLint flat config (react-hooks/rules-of-hooks = error) + Prettier;
tsconfig.test.json so tsc -b type-checks the tests; removed 3 dead deps; npm audit
fix (8 -> 3). Suite 195 -> 247 (happy-path auth, FIFO oldest-first, flakiness fixes),
isolated on app_test via .env.test with a hard-throw setup guard.

Gates: tsc 0 | build 0 | vitest 247/247 | eslint 0 errors.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/admin/pages/Settings.tsx

@@ -311,11 +311,6 @@ export default function Settings() {
     setSysFormInitialized(true);
   }, [sysSettingsData, sysFormInitialized]);
 
-  // ── Early return after all hooks ──
-  if (!canAccessSettings) {
-    return <Navigate to="/" replace />;
-  }
-
   const saveSystemSettingsMutation = useApiMutation<
     typeof sysForm,
     { message?: string; error?: string }
@@ -400,6 +395,11 @@ export default function Settings() {
     },
   });
 
+  // ── Early return after all hooks ──
+  if (!canAccessSettings) {
+    return <Navigate to="/" replace />;
+  }
+
   const handleSaveSystemSettings = async () => {
     try {
       await saveSystemSettingsMutation.mutateAsync(sysForm);