feat: initialize frontend with React and Vite setup

- Add main application structure with App component
- Implement state management for counter functionality
- Create CSS styles for application layout and components
- Include assets for logos and hero image
- Set up Vite configuration for development environment
- Establish global CSS variables for theming

backend/app/db/session.py

@@ -0,0 +1,10 @@
+from sqlalchemy import create_engine
+from sqlalchemy.orm import sessionmaker, declarative_base
+import os
+
+DATABASE_URL = os.getenv("DATABASE_URL")
+
+engine = create_engine(DATABASE_URL)
+SessionLocal = sessionmaker(bind=engine, autocommit=False, autoflush=False)
+
+Base = declarative_base()