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/views/auth/LoginView.vue

@@ -1,6 +1,5 @@
 <template>
   <div class="bg-white rounded-2xl shadow-sm border border-gray-200 p-8 w-full">
-    <!-- Step: password -->
     <template v-if="step === 'password'">
       <h2 class="text-2xl font-semibold text-gray-900 mb-6">Sign in to DocuVault</h2>
 
@@ -38,7 +37,6 @@
           <label for="remember-me" class="text-sm text-gray-600">Stay signed in for 30 days</label>
         </div>
 
-        <!-- Form-level error -->
         <div
           v-if="error"
           class="p-3 rounded-lg bg-red-50 border border-red-200 text-sm text-red-700"
@@ -70,7 +68,6 @@
       </form>
     </template>
 
-    <!-- Step: TOTP -->
     <template v-else-if="step === 'totp'">
       <h2 class="text-2xl font-semibold text-gray-900 mb-1">Two-factor authentication</h2>
       <p class="text-sm text-gray-500 mb-6">Enter the 6-digit code from your authenticator app.</p>
@@ -88,7 +85,6 @@
           />
         </div>
 
-        <!-- Form-level error -->
         <div
           v-if="error"
           class="p-3 rounded-lg bg-red-50 border border-red-200 text-sm text-red-700"
@@ -127,7 +123,6 @@
       </form>
     </template>
 
-    <!-- Step: backup code -->
     <template v-else-if="step === 'backup'">
       <h2 class="text-2xl font-semibold text-gray-900 mb-1">Two-factor authentication</h2>
       <p class="text-sm text-gray-500 mb-6">Enter a backup code.</p>
@@ -144,7 +139,6 @@
           />
         </div>
 
-        <!-- Form-level error -->
         <div
           v-if="error"
           class="p-3 rounded-lg bg-red-50 border border-red-200 text-sm text-red-700"
@@ -195,7 +189,6 @@ const authStore = useAuthStore()
 const router = useRouter()
 const route = useRoute()
 
-// Form state
 const email = ref('')
 const password = ref('')
 const totpInput = ref('')
@@ -204,7 +197,6 @@ const loading = ref(false)
 const error = ref(null)
 const rememberMe = ref(false)
 
-// Step: 'password' | 'totp' | 'backup'
 const step = ref('password')
 
 function resetToPassword() {