Add contributing guidelines to CONTRIBUTING.md

This document provides guidelines for contributing to the SecSuite project, including setup instructions, common tasks, pre-commit hooks, and branching strategies.

Author: Magic-Man-us

CONTRIBUTING.md

@@ -0,0 +1,39 @@
+# Contributing
+
+Thank you for helping improve SecSuite! This short guide gets you up and running quickly.
+
+Developer quick-start
+---------------------
+
+1. Install `uv` (if you don't have it). Follow platform-specific instructions at https://docs.astral.sh/uv/.
+
+2. Sync the development environment and install dev dependencies:
+
+```bash
+make install
+```
+
+3. Common tasks
+
+- Run tests: `make test` or `./scripts/dev pytest`
+- Run lint: `make lint` or `./scripts/dev ruff check .`
+- Type check: `make type` or `./scripts/dev mypy src`
+- Build docs: `make docs` or `./scripts/dev sphinx-build -b html docs docs/_build`
+
+Pre-commit
+----------
+
+Install pre-commit hooks locally:
+
+```bash
+make precommit
+```
+
+Branching and PRs
+------------------
+
+- Create a branch for your feature/fix: `git checkout -b feature/thing`
+- Run tests and linters locally before opening a PR.
+- Open a PR against `main` and include a short description of the change and why.
+
+Thank you! Keep changes small and focused and include tests for new behavior.