Adds a schema_migrations table that records which migration files
have been applied. On boot, only new migrations execute — previously
applied ones are skipped. This eliminates:
- Re-running all 33 migrations on every restart
- Risk of non-idempotent DDL failing on restart
- Unnecessary log noise from re-applying unchanged schema
First boot auto-populates the tracking table with all existing
migrations. Subsequent boots only apply new ones.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>