🔧 Add example environment variables for server configuration

code/websites/pokedex.online/server/.env.example

@@ -0,0 +1,17 @@
+# Environment Variables for Production
+
+# Challonge OAuth Configuration
+CHALLONGE_CLIENT_ID=your_client_id_here
+CHALLONGE_CLIENT_SECRET=your_client_secret_here
+REDIRECT_URI=https://yourdomain.com/oauth/callback
+
+# Server Configuration
+PORT=3000
+NODE_ENV=production
+FRONTEND_URL=https://yourdomain.com
+
+# Session Security
+SESSION_SECRET=generate_a_random_secret_key_here
+
+# Optional: Logging Level
+LOG_LEVEL=info