feat: add Docker support and update backend dependencies

- Introduced `requirements.docker.txt` for Docker-specific dependencies.
- Updated `requirements.txt` to include `psycopg[binary]` and `python-multipart`.
- Enhanced test suite in `test_main_endpoints.py` to cover document CRUD operations.
- Modified `docker-compose.yml` to include PostgreSQL and frontend services.
- Added Nginx configuration for reverse proxying API requests.
- Refactored file handling in Vue components to support new document storage backend.
- Created new utility functions in `docsApi.js` for document management.
- Updated configuration to support new API endpoints for document operations.
- Adjusted Vite configuration to proxy API requests to the local backend.

.dockerignore

@@ -0,0 +1,8 @@
+node_modules
+dist
+htmlcov
+.pytest_cache
+.git
+docker-data
+backend/__pycache__
+backend/tests/__pycache__