refactor: remove build artifacts, caches, and test artifacts

Remove auto-generated and non-essential files:
- Build distribution artifacts (dist/ directories)
- Test and coverage reports (coverage/, .type-coverage/)
- macOS system files (.DS_Store)
- Node.js build cache (.cache/v24.10.0-*)
- Build checkpoint and test config files

These files can be safely regenerated as needed.

Author: jdalton