When multiple bd commands are run in parallel, they can race during database
migrations, causing "duplicate column name" errors. This happens because:
1. Process A checks if column exists → false
2. Process B checks if column exists → false
3. Process A adds column → succeeds
4. Process B adds column → FAILS (duplicate column)
Changes:
- Wrap RunMigrations in BEGIN EXCLUSIVE transaction to serialize migrations
- Disable foreign keys BEFORE the transaction (PRAGMA must be called outside tx)
- Convert nested BEGIN/COMMIT in migrations 010, 022, 025 to use SAVEPOINTs
(SQLite does not support nested transactions)
- Remove redundant PRAGMA foreign_keys calls from individual migrations
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
- Created migrations/ subdirectory with 14 individual migration files
- Reduced migrations.go from 680 to 98 lines (orchestration only)
- Updated test imports to use migrations package
- Updated MULTI_REPO_HYDRATION.md documentation
- All tests passing
