* fix(migrations): use HINDSIGHT_API_MIGRATION_DATABASE_URL when set
Session-level advisory locks are broken when the database URL goes
through PgBouncer in transaction mode: the backend connection is
returned to the pool on COMMIT, orphaning the lock, so multiple pods
can simultaneously run migrations for the same schema.
When HINDSIGHT_API_MIGRATION_DATABASE_URL is set, use it for both
the advisory lock connection and the Alembic run. Callers should
point this at the direct PostgreSQL endpoint (bypassing the pooler)
so the session-level lock is held for the full migration duration.
* refactor(migrations): move MIGRATION_DATABASE_URL to standard config
Wire HINDSIGHT_API_MIGRATION_DATABASE_URL through HindsightConfig
instead of reading os.getenv() directly in migrations.py. Add the
field to the dataclass, from_env(), log_config(), all call sites,
.env.example, and the configuration docs page.
* fix: update test mocks for migration_database_url kwarg and regenerate docs skill
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Co-authored-by: Nicolò Boschi <boschi1997@gmail.com>
dffb87080f