Add initial project configuration and setup for Reference Board Viewer application. Include EditorConfig for consistent coding styles, pre-commit hooks for linting and formatting, Docker Compose for local development with PostgreSQL and MinIO, and a Nix flake for development environment management. Establish CI/CD pipeline for automated testing and deployment.

backend/app/core/__init__.py

@@ -0,0 +1,2 @@
+"""Core application modules."""
+