- Introduced `pyproject.toml` to centralize backend tool configurations (e.g., Ruff, mypy, coverage, pytest).
- Replaced Black, isort, and Flake8 with Ruff for linting, formatting, and import sorting.
- Updated `requirements.txt` to include Ruff and remove replaced tools.
- Added `Makefile` to streamline development workflows with commands for linting, formatting, type-checking, testing, and cleanup.
- Introduced extensive tests for session cleanup, async session CRUD methods, and concurrent cleanup to ensure reliability and efficiency.
- Enhanced `schemas/users.py` with reusable password strength validation logic.
- Improved error handling in `admin.py` routes by replacing `detail` with `message` for consistency and readability.
- Refactored all `password reset` and `auth dependency` tests to utilize async patterns for compatibility with async database sessions.
- Enhanced test fixtures with `pytest-asyncio` to support asynchronous database operations.
- Improved user handling with async context management for `test_user` and `async_mock_user`.
- Introduced `await` syntax for route calls, token generation, and database transactions in test cases.
- Introduced unit tests for `EmailService` covering `ConsoleEmailBackend` and `SMTPEmailBackend`.
- Added tests for password reset request and confirmation endpoints, including edge cases and error handling.
- Implemented soft delete CRUD tests to validate `deleted_at` behavior and data exclusion in queries.
- Enhanced API tests for email functionality and user management workflows.
- Introduced `CRUDBaseAsync` for reusable async operations.
- Configured async database connection using SQLAlchemy 2.0 patterns with `asyncpg`.
- Added `deleted_at` column and soft delete functionality to the `User` model, including related Alembic migration.
- Optimized queries by adding composite indexes for common user filtering scenarios.
- Extended tests: added cases for token-based security utilities and user management endpoints.
