Final schema in database/init.sql: 8 tables with foreign keys, cascading deletes, unique constraints, and indexes. Tables: service, incident, incident_update, incident_service, maintenance, maintenance_service, subscriber (with partial unique indexes), metric (with composite index on service_id + recorded_at). Status enums enforced at application level.
Commit: bd4a46b (Phase 2), 2854f43 (Phase 4 — added metric table)
- SQL Schema: https://dbdiagram.io/d/643dab996b31947051bf53e7
- Mock: