No database - all marketplace state is ephemeral mock data

[Mosss-OS]

Description

The backend has no database. All marketplace state is:

• In-memory mock data (MOCK_MARKETPLACES array that resets on restart)
• On-chain (contract state)
• Environment variables

Impact

• Server restart loses all marketplace records
• No querying, filtering, or search capability beyond in-memory operations
• No user data persistence (profiles saved to localStorage only)
• No analytics data collection
• No transaction history

Suggested Fix

Add a database (PostgreSQL would fit well). Start with:

• User profiles
• Marketplace metadata (name, description, category, owner)
• Deployment records (address, chain, tx hash, timestamp)
• Analytics events
• Canvas/template storage