- Enforced minimum length and security standards for `SECRET_KEY` (32 chars, random value required in production).
- Added checks for strong `FIRST_SUPERUSER_PASSWORD` (min 12 chars with mixed case, digits).
- Updated `.env.template` with guidelines for secure configurations.
- Added `test_config.py` to verify validations for environment configurations, passwords, and database URLs.
This commit introduces a suite of tests for user models, schemas, CRUD operations, and authentication services. It also adds utilities for in-memory database setup to support these tests and updates environment settings for consistency.
