fix(admin-web): maintenance page API path mismatches + base proxy route

- maintenance page: 'status' → 'full' (GET /settings/maintenance/full)
- maintenance page: 'mode' POST → '' PUT (PUT /settings/maintenance)
- Add maintenance base route.ts for root-level GET/PUT proxy

dashboards/admin-web/src/app/(dashboard)/maintenance/page.tsx

@@ -59,7 +59,7 @@ export default function MaintenancePage() {
 
   const loadData = useCallback(async () => {
     setLoading(true);
-    const data = await apiFetch('status');
+    const data = await apiFetch('full');
     if (data?.mode) {
       setStatus(data);
       setNewMode(data.mode);
@@ -74,8 +74,8 @@ export default function MaintenancePage() {
 
   async function handleSave() {
     setSaving(true);
-    await apiFetch('mode', {
-      method: 'POST',
+    await apiFetch('', {
+      method: 'PUT',
       body: JSON.stringify({ mode: newMode, message: newMessage || undefined }),
     });
     setSaving(false);

dashboards/admin-web/src/app/api/maintenance/route.ts

@@ -0,0 +1,39 @@
+/**
+ * Maintenance base route — handles GET /api/maintenance and PUT /api/maintenance.
+ * Maps to platform-service GET /api/settings/maintenance and PUT /api/settings/maintenance.
+ */
+
+import { NextRequest, NextResponse } from 'next/server';
+import { getCurrentUserFromRequest } from '@/lib/auth-server';
+import { logError } from '@/lib/logger';
+
+const PLATFORM_URL = process.env.PLATFORM_SERVICE_URL || 'http://localhost:4003';
+
+async function proxyBase(req: NextRequest) {
+  try {
+    const caller = await getCurrentUserFromRequest(req);
+    if (!caller) return NextResponse.json({ error: 'Unauthorized' }, { status: 401 });
+    const qs = new URL(req.url).search;
+    const headers: Record<string, string> = {
+      'Content-Type': 'application/json',
+      'x-request-id': req.headers.get('x-request-id') || crypto.randomUUID(),
+      'x-user-id': caller.id,
+      'x-product-id': req.headers.get('x-product-id') || process.env.PRODUCT_ID || 'lysnrai',
+    };
+    const fetchOptions: RequestInit = { method: req.method, headers };
+    if (req.method !== 'GET' && req.method !== 'HEAD') fetchOptions.body = await req.text();
+    const res = await fetch(`${PLATFORM_URL}/api/settings/maintenance${qs}`, fetchOptions);
+    const data = await res.json().catch(() => null);
+    return NextResponse.json(data ?? { error: res.statusText }, { status: res.status });
+  } catch (error) {
+    logError('Maintenance base proxy error', error);
+    return NextResponse.json({ error: 'Service unavailable' }, { status: 502 });
+  }
+}
+
+export async function GET(req: NextRequest) {
+  return proxyBase(req);
+}
+export async function PUT(req: NextRequest) {
+  return proxyBase(req);
+}