fix: apply ruff auto-fixes and add hk git hooks

- Fix pre-existing lint errors in engine/ modules using ruff --unsafe-fixes
- Add hk.pkl with pre-commit and pre-push hooks using ruff builtin
- Configure hooks to use 'uv run' prefix for tool execution
- Update mise.toml to include hk and pkl tools
- Use 'hk install --mise' for proper mise integration
- All 73 tests pass

README.md

@@ -155,3 +155,4 @@ msg = poller.get_active_message()  # returns (title, body, timestamp) or None
 ---
 
 *macOS only (script/system font paths for translation are hardcoded). Primary display font is user-selectable via the bundled `fonts/` picker. Python 3.9+.*
+# test