Per plan §13.3, implements user-requested AI replay commentary with:
- HMAC bot authentication via shared_secret
- Rate limiting: 5 requests/day per bot
- Match validation (exists and completed)
- Idempotency via enrichment_requested_at column
- Enqueues to Valkey for acb-enrichment service
- Returns 202 Accepted with estimated wait time
Also adds:
- AllowN() method to ratelimit package for multi-token checks
- enrichment_requested_at column to matches table (idempotency)
- enrichLtr rate limiter (5/day per bot)
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Adds ratelimit package with per-IP and per-key HTTP middleware.
Applied to register (5/hr), feedback (20/hr), predict (60/hr),
and job submission (5/day) endpoints. Includes metrics counter
for rejected requests and periodic bucket cleanup goroutine.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
