fix: Incomplete URL substring sanitization

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src/routes/apiKeys.ts

···
         });
       }
 
-      const isGemini = fullApiUrl.includes('generativelanguage.googleapis.com');
+      const isGemini = parsedUrl.hostname === 'generativelanguage.googleapis.com';
 
       if (isGemini) {
         const listModelsUrl = `https://generativelanguage.googleapis.com/v1beta/models?key=${apiKey}`;