Convert to database-first configuration with token storage

- Rename config.json → seed.json to clarify seeding purpose
- Update ConfigManager to be database-first with minimal file fallbacks
- Store Discord token in database instead of environment variables
- Remove allowedSfxChannels functionality completely
- Update seeding script to import token from seed.json to database
- Add token field to bot_config table in database schema
- Update Docker volume mount to use seed.json
- Update gitignore to protect seed.json while allowing seed.example.json

Configuration Flow:
1. First run: Import from seed.json to database (one-time seeding)
2. Runtime: All configuration from SQLite database
3. Fallback: Environment variables if database unavailable

Security: All sensitive data now stored in encrypted SQLite database

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

package.json

@@ -32,7 +32,7 @@
     "restart": "docker compose restart",
     "logs": "docker compose logs -f",
     "boom": "pnpm stop && pnpm build && pnpm start",
-    "reset-db": "pnpm stop && rm -f data/ghbot.db data/ghbot.db-shm data/ghbot.db-wal && echo 'Database reset complete. Run pnpm start to re-seed from config.json'",
+    "reset-db": "pnpm stop && rm -f data/*.db* && echo 'Database reset complete. Run pnpm start to re-seed from seed.json'",
     "image:build": "docker build -t ghbot:${VERSION:-latest} .",
     "image:run": "docker run -d --name ghbot --restart always ghbot:${VERSION:-latest}"
   },