- Create project.ts with all project commands: list, add, remove, show, set-default, detect
- Implement runProjectList() with default project highlighting
- Implement runProjectAdd() with validation for name, path, isolation mode
- Implement runProjectRemove() with confirmation prompt and --force flag
- Implement runProjectShow() with project details and health info
- Implement runProjectSetDefault() to set default project
- Implement runProjectDetect() to show project from CWD
- Add project.test.ts with basic function export tests
- Add optional globalDir parameter to resolveProject(), getDefaultProject(),
setDefaultProject(), and clearDefaultProject() for test isolation
- Remove ESLint suppression by using void operator for intentionally unused var
- Update all tests to use isolated globalDir parameter
- Complete tests for default project resolution
