refactor(09-05): CODE-09 purge — Phase 9 files (WHAT comments removed)

Frontend: AdminLayout, AdminSidebar, AdminOverviewView, AdminUsersView,
AdminQuotasView, AdminAiView, AdminAuditView, router/index.js, LoginView,
tailwind.config.js, api/admin.js — WHAT labels stripped; WHY constraints
preserved (D-16 anchors, security notes, api_key write-only invariant,
router guard rationale, D-08/D-09/D-10 decision refs, fetchWithRetry reason).
Backend: overview.py was already clean (no WHAT comments present).
Frontend: 137 tests pass, build succeeds.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

frontend/src/router/index.js

@@ -15,7 +15,6 @@ const routes = [
   { path: '/document/:id', component: DocumentView },
   { path: '/settings', component: SettingsView },
 
-  // Phase 2 — public auth routes (no guard)
   {
     path: '/login',
     component: () => import('../views/auth/LoginView.vue'),
@@ -37,7 +36,6 @@ const routes = [
     meta: { public: true, layout: 'auth' },
   },
 
-  // Phase 2 — authenticated routes
   { path: '/account', redirect: '/settings' },
 
   // Admin panel — standalone route subtree with AdminLayout as the route component.
@@ -56,7 +54,6 @@ const routes = [
     ],
   },
 
-  // Cloud storage overview and folder browser
   {
     path: '/cloud',
     name: 'cloud',
@@ -70,7 +67,6 @@ const routes = [
     meta: { requiresAuth: true },
   },
 
-  // Phase 4 — folder and sharing routes
   {
     path: '/folders/:folderId',
     name: 'folder',
@@ -96,7 +92,6 @@ const router = createRouter({
 router.beforeEach(async (to) => {
   const authStore = useAuthStore()
 
-  // Step 1: ensure access token is present for non-public routes.
   if (!to.meta.public && !authStore.accessToken) {
     try {
       await authStore.refresh()