Initial commit: Lightning Lottery - Bitcoin Lightning Network powered lottery

Features:
- Lightning Network payments via LNbits integration
- Provably fair draws using CSPRNG
- Random ticket number generation
- Automatic payouts with retry/redraw logic
- Nostr authentication (NIP-07)
- Multiple draw cycles (hourly, daily, weekly, monthly)
- PostgreSQL and SQLite database support
- Real-time countdown and payment animations
- Swagger API documentation
- Docker support

Stack:
- Backend: Node.js, TypeScript, Express
- Frontend: Next.js, React, TailwindCSS, Redux
- Payments: LNbits

front_end/env.example

@@ -0,0 +1,40 @@
+# Lightning Lottery Frontend - Environment Configuration
+# Copy this file to .env.local and fill in your values
+
+# ======================
+# Server Configuration
+# ======================
+# Port for Next.js development server (default: 3001)
+PORT=3001
+
+# ======================
+# API Configuration
+# ======================
+# Backend API base URL
+# Development: http://localhost:3000
+# Production: https://api.yourdomain.com
+NEXT_PUBLIC_API_BASE_URL=http://localhost:3000
+
+# Frontend application base URL
+# Development: http://localhost:3001
+# Production: https://yourdomain.com
+NEXT_PUBLIC_APP_BASE_URL=http://localhost:3001
+
+# Backend API fallback port used when the frontend is accessed via a non-localhost host
+# Keep at 3000 if you run the API on the default dev port
+NEXT_PUBLIC_BACKEND_PORT=3000
+
+# ======================
+# Optional: Admin Configuration
+# ======================
+# Only needed if you want to use admin features from the frontend
+# NEXT_PUBLIC_ADMIN_KEY=your_admin_api_key_here
+
+# ======================
+# Notes
+# ======================
+# - Copy this file to .env.local for local development
+# - All variables that need to be accessible in the browser must start with NEXT_PUBLIC_
+# - Never expose sensitive keys in production frontend
+# - PORT is read by the npm scripts to set the dev server port
+# - Restart the dev server after changing .env.local