Implement REST API

[superposition]

Description

Add REST endpoints for initial data loading.

Tasks

• Add HTTP routes to Bun server
• GET /api/playlist - return historical snapshots list
• GET /api/snapshot/:id - return single snapshot
• GET /api/pools - return current pool states
• GET /api/health - health check endpoint
• Add CORS headers for web client
• Add response compression (gzip)

Acceptance Criteria

• All endpoints return correct data
• CORS allows web client access
• Responses are compressed

Labels

web-app, backend, server