- Updated the `Guard` class to improve permission checking by utilizing the new `Permission` class.
- Refactored tests in `authorize.spec.ts` to use `Permission` instances instead of strings for better type safety.
- Introduced a new `permissions.spec.ts` file to test the functionality of the `Permission` and `Policy` classes.
- Enhanced the `recursivelyReplacePlaceholders` utility function to support various object structures and types.
- Updated middleware and controller files to align with the new permission handling structure.
