Without this, when the local admin gate fires on friend-add, the user
got a generic 'Could not send friend request' fallback. Now they see
'Your admin needs to approve federation with this instance' with a
pointer to Connections settings where Task 12's pending-approvals
section shows their queued request.
Removes try/catch on the deleted InstanceNotConnectedError/Disconnected
classes (T17). Server now returns structured error codes; client maps
them to human-readable toasts via the new mapServerErrorToMessage helper.
The friend-add flow no longer triggers ConnectInstanceModal — the server
handles all routing/peering/lookup. The modal itself stays for Connections
settings and space-join flows.
Jannis Braun