[STORY 3.1] Secure AI Edge Proxy Gateway

[RamonRiosJr]

📝 Description

Remove the Gemini SDK bundle from the frontend to drastically reduce client-side footprint, and expose a secure serverless gateway protecting keys from browser extraction.

🎯 Acceptance Criteria

• Build /api/chat Route Handler deployed to Vercel/Netlify Edge
• Move Google Gemini SDK execution exclusively to the server
• Construct dynamic system prompt injecting the card owner's bio/skills natively
• Ensure the frontend application contains zero API keys