ops: deploy self-healer to Hetzner (commits 064232a–7304aa8)

[dennisonbertram]

Three commits are on main but not yet live on the server:

• `064232a` — self-healer: 30s interval, liveness probes, auto circuit recovery
• `f2a9a60` — build log + session docs
• `7304aa8` — CLAUDE.md, CHANGELOG, test framework, CI

Deploy steps:

1. SSH to server, pull latest, `CGO_ENABLED=1 go build -o bin/ah ./cmd/ah`
2. Copy binary, `systemctl restart ah.service`
3. Verify log: `reconciler: starting (interval=30s)`
4. Verify migration: `SELECT circuit_retry_at FROM services LIMIT 1` returns without error
5. `docker inspect` a running service — confirm HealthCheck is present