docs: add CONTRIBUTING.md

Closes #40

Author: MiniCodeMonkey

CONTRIBUTING.md

@@ -0,0 +1,49 @@
+# Contributing to Chief
+
+Thanks for your interest in contributing to Chief! Here's how to get started.
+
+## Prerequisites
+
+- [Go 1.24+](https://go.dev/dl/)
+- [Claude Code CLI](https://docs.anthropic.com/en/docs/claude-code) (for end-to-end testing)
+- [golangci-lint](https://golangci-lint.run/welcome/install-local/) (optional, for linting)
+
+## Getting Started
+
+```bash
+git clone https://github.com/minicodemonkey/chief.git
+cd chief
+make build
+```
+
+## Development Workflow
+
+```bash
+make build       # Build the binary to ./bin/chief
+make test        # Run all tests
+make lint        # Run linters
+make fmt         # Format code
+make vet         # Run go vet
+make run         # Build and run the TUI
+```
+
+## Submitting Changes
+
+1. Fork the repository
+2. Create a feature branch (`git checkout -b my-feature`)
+3. Make your changes
+4. Run `make test` and `make lint` to verify
+5. Commit using [conventional commits](https://www.conventionalcommits.org/) (e.g. `feat:`, `fix:`, `docs:`)
+6. Open a pull request against `main`
+
+## Reporting Bugs
+
+Open an issue on [GitHub Issues](https://github.com/minicodemonkey/chief/issues) with:
+
+- Steps to reproduce
+- Expected vs actual behavior
+- Chief version (`chief --version` or `git describe --tags`)
+
+## License
+
+By contributing, you agree that your contributions will be licensed under the [MIT License](README.md#license).