fix: reduce maxDuration to 300s for Vercel hobby plan

Vercel hobby plan limits serverless functions to 300 seconds max.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/app/api/generate/route.ts

@@ -17,7 +17,7 @@ import { GenerateRequest, GenerateResponse, ModelType, SelectedModel, ProviderTy
 import { GenerationInput, GenerationOutput, ProviderModel } from "@/lib/providers/types";
 import { uploadImageForUrl, shouldUseImageUrl, deleteImages } from "@/lib/images";
 
-export const maxDuration = 600; // 10 minute timeout for video generation (Vercel only)
+export const maxDuration = 300; // 5 minute timeout (Vercel hobby plan limit)
 export const dynamic = 'force-dynamic'; // Ensure this route is always dynamic
 
 // Map model types to Gemini model IDs