New endpoints for Trinity Console:
- GET /admin/discord/audit — Full server audit (channels, roles, structure)
- GET /admin/discord/channels — Just channels
- GET /admin/discord/roles — Just roles
Returns:
- Server info (name, member count, features)
- Categories with nested children
- Orphan channels (not in categories)
- Role hierarchy with positions and member counts
- Permission overwrites per channel
Uses existing Discord.js client from app.locals.
Chronicler #70
e99ef3b942