chore(env): streamline .env and .env.example configuration files

.env.example

@@ -1,8 +1,9 @@
-# Django Production Settings
+# Mode Selection (DEV=true for local dev, DEV=false for live production)
+DEV=false
+
+# Django Settings
 DJANGO_SECRET_KEY=generate-a-strong-random-secret-key-here
-DJANGO_DEBUG=False
-ALLOWED_HOSTS=*
-CORS_ALLOW_ALL_ORIGINS=True
+ALLOWED_HOSTS=localhost,127.0.0.1,YOUR_SERVER_IP
 CSRF_TRUSTED_ORIGINS=http://localhost,http://127.0.0.1,http://YOUR_SERVER_IP
 
 # Database Configuration (PostgreSQL)
@@ -16,7 +17,7 @@ POSTGRES_PORT=5432
 REDIS_URL=redis://redis:6379/0
 
 # LLM Config (OpenAI / OpenRouter)
-OPENAI_API_KEY=sk-or-v1-your-openrouter-key
+OPENAI_API_KEY=sk-or-v1-your-openrouter-key-here
 OPENAI_MODEL=google/gemma-4-26b-a4b-it:free
 
 # Telegram Config