## 1. Schema & Queries

- [x] 1.1 `db/schema.sql`: idempotent `ALTER TABLE scans ADD COLUMN IF NOT EXISTS ip TEXT;`; `make db-up`
- [x] 1.2 `queries.sql`: `GetOrderByID` (:one), `CountAlertsByTagSince` (:one, tag_id + since → count of alert_sent), `CountAlertsByIPSince` (:one, ip + since); `make generate`; build

## 2. Gating & Limits

- [x] 2.1 `scan.go`: capture client IP (X-Forwarded-For → RemoteAddr host); pass IP into `InsertScan`
- [x] 2.2 `shouldAlert`: add paid-gating (order exists && status != 'paid' → false), per-tag daily cap (default 5, env ALERT_MAX_TAG_DAY), per-IP hourly cap (default 10, env ALERT_MAX_IP_HOUR) — checked in that order

## 3. Verification

- [x] 3.1 Extend verify suite: lapsed-order tag → no alert; paid-order tag → alert; no-order tag → alert; tag over daily cap → no alert; IP over hourly cap → no alert
- [x] 3.2 Existing suites (Phase 1/2/2.5) still pass on fresh DB
- [x] 3.3 `openspec validate scan-limits-gating`; commit