Refactor test_pin_lock.py to use Pydantic objects instead of mocks

- Replace complex mocking with actual Pydantic model instances
- Use real SiliconConfig, PadConfig, and other model classes
- Simplify tests while maintaining coverage
- Properly test parse_component_path function

These changes make the tests more accurate by testing against the actual Pydantic
model structures rather than complex mocks.

Author: robtaylor