Implement GuardDen Discord moderation bot

Features:
- Core moderation: warn, kick, ban, timeout, strike system
- Automod: banned words filter, scam detection, anti-spam, link filtering
- AI moderation: Claude/OpenAI integration, NSFW detection, phishing analysis
- Verification system: button, captcha, math, emoji challenges
- Rate limiting system with configurable scopes
- Event logging: joins, leaves, message edits/deletes, voice activity
- Per-guild configuration with caching
- Docker deployment support

Bug fixes applied:
- Fixed await on session.delete() in guild_config.py
- Fixed memory leak in AI moderation message tracking (use deque)
- Added error handling to bot shutdown
- Added error handling to timeout command
- Removed unused Literal import
- Added prefix validation
- Added image analysis limit (3 per message)
- Fixed test mock for SQLAlchemy model

docker-compose.yml

@@ -0,0 +1,44 @@
+services:
+  bot:
+    build: .
+    container_name: guardden-bot
+    restart: unless-stopped
+    depends_on:
+      db:
+        condition: service_healthy
+    environment:
+      - GUARDDEN_DISCORD_TOKEN=${GUARDDEN_DISCORD_TOKEN}
+      - GUARDDEN_DATABASE_URL=postgresql://guardden:guardden@db:5432/guardden
+      - GUARDDEN_LOG_LEVEL=${GUARDDEN_LOG_LEVEL:-INFO}
+      - GUARDDEN_AI_PROVIDER=${GUARDDEN_AI_PROVIDER:-none}
+      - GUARDDEN_ANTHROPIC_API_KEY=${GUARDDEN_ANTHROPIC_API_KEY:-}
+      - GUARDDEN_OPENAI_API_KEY=${GUARDDEN_OPENAI_API_KEY:-}
+    volumes:
+      - ./data:/app/data
+    networks:
+      - guardden
+
+  db:
+    image: postgres:15-alpine
+    container_name: guardden-db
+    restart: unless-stopped
+    environment:
+      - POSTGRES_USER=guardden
+      - POSTGRES_PASSWORD=guardden
+      - POSTGRES_DB=guardden
+    volumes:
+      - postgres_data:/var/lib/postgresql/data
+    healthcheck:
+      test: ["CMD-SHELL", "pg_isready -U guardden -d guardden"]
+      interval: 5s
+      timeout: 5s
+      retries: 5
+    networks:
+      - guardden
+
+networks:
+  guardden:
+    driver: bridge
+
+volumes:
+  postgres_data: