Add pre-commit hooks for Ruff formatting and linting

Signed-off-by: Tony Lin <tony.lin@intel.com>

.pre-commit-config.yaml

@@ -0,0 +1,7 @@
+repos:
+  - repo: https://github.com/astral-sh/ruff-pre-commit
+    rev: v0.15.0
+    hooks:
+      - id: ruff-check
+        args: [--fix]
+      - id: ruff-format

CONTRIBUTING.md

@@ -6,6 +6,18 @@ Run all commands below from the repository root. See [README.md](README.md) for
 
 Before committing, format the modified code and pass the corresponding checks.
 
+### Pre-commit
+
+Install [pre-commit](https://pre-commit.com/) and enable the Git hook in your local clone:
+
+```bash
+python -m pip install pre-commit
+pre-commit install
+pre-commit run --all-files  # Optional: check the whole repository
+```
+
+The hook runs Ruff checks and formatting on staged Python files. If it changes a file, review and stage the changes before committing again. Each contributor must install the hook in their own clone.
+
 ### Python
 
 Ruff is configured in [pyproject.toml](pyproject.toml).