Adds backend/src/db/migrations-runner.js:
- Tracks applied migrations in _migrations table
- Applies .sql files from src/db/migrations/ in alphabetical order
- Each file runs in a transaction — fail-fast, no partial state
- `migrate:bootstrap` marks 000_baseline.sql as applied on existing DBs
000_baseline.sql — full schema snapshot from prod DB (168 objects, 2026-05-06).
Removed stale PostgreSQL migration files (001_init.sql, 002_constraints.sql)
that used SERIAL/EXTENSION syntax incompatible with SQLite.
npm scripts:
migrate → migrations-runner.js (versioned)
migrate:bootstrap → mark baseline applied (run once per env)
migrate:legacy → legacy migrate.js (kept for reference)
On prod DB after `migrate:bootstrap`: "Nothing to apply — schema is up to date".
Legacy migrate.js still in place; tests still use it via setup.js (unchanged).
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Maxim Dolgolyov