enhance security and performance: add rate limiting, session validation, and logging; update environment variables

.env.example

@@ -2,12 +2,21 @@
 PORT=3000
 NODE_ENV=production
 BASE_URL=https://loot-hunt.com
+TRUST_PROXY=false
 
 # Session
-SESSION_SECRET=change-me-to-a-random-string
+SESSION_SECRET=change-me-to-a-random-string-at-least-32-characters-long
 
 # Database (SQLite file path)
 DB_PATH=./data/loot-hunt.db
 
 # Uploads directory
 UPLOADS_DIR=./data/uploads
+
+# Logging
+DATA_PATH=./data
+LOG_LEVEL=info
+
+# Rate Limiting
+RATE_LIMIT_WINDOW_MS=900000
+RATE_LIMIT_MAX_REQUESTS=100