feat: improve performance with cache and proper indexing

CONTRIBUTING.md

@@ -1,81 +0,0 @@
-# Contributing to morbac_pg
-
-Thank you for your interest in contributing to morbac_pg!
-
-## How to Contribute
-
-### Reporting Bugs
-
-If you find a bug, please open an issue with:
-- A clear description of the bug
-- Steps to reproduce
-- Expected vs actual behavior
-- PostgreSQL version
-- Relevant logs or error messages
-
-### Suggesting Features
-
-Feature requests are welcome! Please open an issue describing:
-- The use case or problem you're trying to solve
-- How the feature would work
-- Whether it aligns with Multi-OrBAC model principles
-
-### Code Contributions
-
-1. **Fork the repository**
-2. **Create a feature branch**: `git checkout -b feature/my-feature`
-3. **Make your changes**:
-   - Follow the existing code style (SQL formatting, naming conventions)
-   - Add tests in `test_morbac.sql` for new features
-   - Update `DOCUMENTATION.md` if adding new functionality
-4. **Test your changes**: `make test`
-5. **Commit with clear messages**: `git commit -m "Add feature: description"`
-6. **Push to your fork**: `git push origin feature/my-feature`
-7. **Open a Pull Request** with a description of your changes
-
-### Code Style Guidelines
-
-- **SQL**: Use uppercase for keywords, lowercase for identifiers
-- **Naming**: Use snake_case for tables, columns, functions
-- **Schema**: All objects must be in the `morbac` schema
-- **Comments**: Add comments for complex logic
-- **Functions**: Include COMMENT ON statements for public functions
-
-### Testing
-
-All changes must include tests:
-- Add test cases to `test_morbac.sql`
-- Ensure all existing tests still pass
-- Test against PostgreSQL 12+ (mention version in PR)
-
-### Documentation
-
-- Update `DOCUMENTATION.md` for API changes
-- Update `CHANGELOG.md` following [Keep a Changelog](https://keepachangelog.com/en/1.0.0/) format
-- Keep `README.md` simple (link to docs instead of expanding it)
-
-## Development Setup
-
-```bash
-# Install PostgreSQL (if not already installed)
-brew install postgresql  # macOS
-# or use your package manager
-
-# Clone your fork
-git clone https://github.com/your-username/morbac_pg.git
-cd morbac_pg
-
-# Install the extension
-make install
-
-# Run tests
-make test
-```
-
-## Questions?
-
-Feel free to open an issue for questions or discussion.
-
-## License
-
-By contributing, you agree that your contributions will be licensed under the MIT License.