Mirrors the REST-login change in f17c46c on the registration insert path.
A successful POST /api/auth/register does not by itself imply a live
WebSocket — the client may never connect (transient network, mobile
background, error path between the 201 and /ws), leaving a permanently
stuck-online row that no disconnect timer can clean up. The schema
default 'offline' is correct; ws/handler.ts flips it to 'online' on real
WS auth.
The federated-stub upgrade path in the same handler is unaffected: it
only updates passwordHash/username/homeUserId/displayName/avatarColor,
leaving the stub's pre-existing 'offline' status (set when the stub was
created via replication) untouched.
Updates docs/systems/auth.md step 7 to reflect the new behavior.
Jannis Braun
4fa2414933