chore: update Docker configuration and improve health check functionality

- Added Docker health check endpoint to the FastAPI application, returning a 200 status when the app is running.
- Updated Dockerfile to include curl for health checks and modified entrypoint script to exit on errors.
- Enhanced .dockerignore and .gitignore files to exclude coverage and test artifacts.
- Updated docker-compose.prod.yml to specify version.
- Added pytest-cov as a development dependency to improve test coverage reporting.

requirements-dev.txt

@@ -1,4 +1,5 @@
 -r requirements.txt
 pytest>=8.0,<9.0
 pytest-asyncio>=1.0,<2.0
+pytest-cov>=6.0,<7.0
 httpx>=0.27,<1.0