Add tests for authentication and utilities, and update dependencies

- Created a new test package for services and added tests for AuthService.
- Implemented tests for user registration, login, and token creation.
- Added a new test package for utilities and included tests for password and JWT utilities.
- Updated `uv.lock` to include new dependencies: bcrypt, email-validator, pyjwt, and pytest-asyncio.

tests/api/__init__.py

@@ -0,0 +1 @@
+"""API tests package."""