- Add `list_directory_filtered` function with ignore logic
- Update `default_gitignore` with common VCS and build patterns
- Integrate ignore filtering into `Workspace.list_dir`
- Rename project to HeroPrompt in README
- Update README features and usage descriptions
- Implement level-scoped .gitignore/.heroignore matching
- Rewrite directory walker to use new ignore matcher
- Replace filemap parser with robust header-based logic
- Support `FILE`, `FILECHANGE`, and legacy header formats
- Add extensive tests for new parsing and ignore features