Add comprehensive test suite for image processing and related services

- Implement tests for database generator to ensure proper session handling.
- Create tests for EXIF extraction and conversion functions.
- Add tests for image-related endpoints, ensuring proper data retrieval and isolation between clients.
- Develop tests for OCR functionality, including language detection and text extraction.
- Introduce tests for the image processing pipeline, covering success and failure scenarios.
- Validate rate limiting functionality and ensure independent counters for different clients.
- Implement scraper tests to verify HTML content fetching and error handling.
- Add unit tests for various services, including storage and filename generation.
- Establish worker entry point for ARQ to handle background image processing tasks.

pytest.ini

@@ -0,0 +1,8 @@
+[pytest]
+asyncio_mode = auto
+testpaths = tests
+python_files = test_*.py
+python_functions = test_*
+filterwarnings =
+    ignore::DeprecationWarning
+