The [S] button only called setDM(false) without navigating away from
/chat area. Since the notes-to-self feature now calls navigate('/dm/:id'),
the URL stayed at /dm/... and ChatArea never re-mounted.
[S] now navigates to /, [@] navigates to /dm.
Frontend:
- Settings link in header next to logout
- [+] button to create server (name + optional icon)
- [#] button to join server via invite code
- [+] button to create channel (name, type, category)
- Server name shown instead of UUID in channel list header
- /invites/:code route wired for JoinServer component
Backend:
- Wire role CRUD + member-role assignment routes (MANAGE_SERVER gated)
- Seed @everyone default role on server creation