Automated Deadlock Prevention and Migration Performance Guardrails

Act as a Database Performance Tuning Expert. Write a ruthless 'Database Migration Security Policy' bash script designed to be executed as a mandatory, blocking linting stage within a [CI_CD_PIPELINE]. The script must parse raw SQL migration files (e.g., `.sql` Flyway files) and algorithmically scan for highly 'dangerous' DDL operations known to cause production outages (e.g., adding a new column with a heavy `DEFAULT` value in older PostgreSQL versions, or executing massive index creations without the `CONCURRENTLY` flag). The script must forcefully inject and enforce a strict session-level [MAX_LOCK_TIMEOUT] (e.g., `SET lock_timeout = '5s'`) at the top of every script to prevent catastrophic queue blocking. Tailor the regex scanning logic specifically to the known online DDL limitations of the [DATABASE_ENGINE] architecture.