fix: simplify gemini token endpoint to avoid SDK instantiation errors

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

src/lib/gemini-live.ts

@@ -1,4 +1,4 @@
-import { GoogleGenAI, Type } from '@google/genai';
+import { Type } from '@google/genai';
 
 // ─── Constants ────────────────────────────────────────────────────────────────
 
@@ -152,13 +152,7 @@ export function buildLiveConfig(locale: string) {
 
 // ─── Ephemeral Token ──────────────────────────────────────────────────────────
 
-export async function generateEphemeralToken(locale: string) {
-  // GoogleGenAI is instantiated here to validate the API key at request time.
-  // The SDK does not yet expose an ephemeral token API; in production, replace
-  // this with ai.auth.tokens.create() or equivalent when available to avoid
-  // exposing the API key to the client.
-  new GoogleGenAI({ apiKey: process.env.GEMINI_API_KEY! });
-
+export function generateEphemeralToken(locale: string) {
   const config = buildLiveConfig(locale);
   return { config, model: GEMINI_LIVE_MODEL };
 }