Revert sqlc v1.30.0 upgrade, regenerate with v1.29.0 (#746)

## Summary
- Someone accidentally ran `sqlc generate` with v1.30.0, bumping the
version comment in all 22 generated files in `api/dbv1/`
- This reverts those files back to v1.29.0

## Test plan
- [x] No logic changes — only the `// sqlc v1.30.0` → `// sqlc v1.29.0`
header comment is affected in each file

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: rickyrombo