chore: update project configuration and documentation

- Added *.egg-info/ to .gitignore to prevent egg metadata from being tracked.
- Updated virtual environment instructions in CONTRIBUTING.md and README.md to use .venv for consistency.
- Revised mkdocs.yml to include a placeholder for the repository URL when publishing.
- Cleaned up pyproject.toml by removing unnecessary pylint configuration.
- Enhanced import-format.md and runbook.md documentation for clarity on user roles and health check endpoints.

CHANGELOG.md

@@ -36,4 +36,4 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Input validation and initData hash verification for Miniapp access.
 - Optional CORS and init_data_max_age; use env for secrets.
 
-[0.1.0]: https://github.com/your-org/duty-teller/releases/tag/v0.1.0
+[0.1.0]: https://github.com/your-org/duty-teller/releases/tag/v0.1.0  <!-- placeholder: set to your repo URL when publishing -->