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/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 {