fix: split gemini-token into GET health check + POST token request

Health check no longer triggers rate limiter, fixing toggle not appearing.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/app/(frontend)/api/gemini-token/route.ts

@@ -4,9 +4,18 @@ import { generateEphemeralToken } from '@/lib/gemini-live';
 // ─── Rate Limiting ────────────────────────────────────────────────────────────
 
 const rateLimitMap = new Map<string, number>();
-const RATE_LIMIT_MS = 60_000; // 1 token per minute per IP
+const RATE_LIMIT_MS = 30_000; // 1 token per 30 seconds per IP
 
-// ─── Route Handler ────────────────────────────────────────────────────────────
+// ─── Health Check (GET — no rate limit) ──────────────────────────────────────
+
+export async function GET() {
+  if (!process.env.GEMINI_API_KEY) {
+    return NextResponse.json({ success: false }, { status: 503 });
+  }
+  return NextResponse.json({ success: true });
+}
+
+// ─── Token Request (POST — rate limited) ─────────────────────────────────────
 
 export async function POST(request: NextRequest) {
   try {
@@ -26,12 +35,10 @@ export async function POST(request: NextRequest) {
     rateLimitMap.set(ip, Date.now());
 
     const { locale } = (await request.json()) as { locale?: string };
-    const result = await generateEphemeralToken(locale === 'fr' ? 'fr' : 'en');
+    const result = generateEphemeralToken(locale === 'fr' ? 'fr' : 'en');
 
     return NextResponse.json({
       success: true,
-      // In production, replace apiKey with an ephemeral token from ai.auth.tokens.create()
-      // to avoid exposing the long-lived API key to the client.
       apiKey: process.env.GEMINI_API_KEY,
       model: result.model,
       config: result.config,

src/components/configurator/ModeToggle.tsx

@@ -24,11 +24,7 @@ export default function ModeToggle({ mode, onChange }: ModeToggleProps) {
       if (!navigator.mediaDevices?.getUserMedia) return;
 
       try {
-        const res = await fetch('/api/gemini-token', {
-          method: 'POST',
-          headers: { 'Content-Type': 'application/json' },
-          body: JSON.stringify({ locale: 'en' }),
-        });
+        const res = await fetch('/api/gemini-token');
         const data = (await res.json()) as { success: boolean };
         if (data.success) setVoiceSupported(true);
       } catch {