fix(federation): include profile snapshots in friend relay events

Replicated user stubs created by resolveOrCreateReplicatedUser had
null avatar/displayName, causing blank profiles in the UI until
page refresh. Friend relay events now carry profile snapshots
(displayName, avatar, avatarColor, banner, bio) so the receiving
instance can hydrate stubs with real data.

packages/shared/src/types.ts

@@ -782,9 +782,19 @@ export interface FederationGroupPayload {
   members: FederationRelayParticipant[];
 }
 
+export interface FederationRelayProfileSnapshot {
+  displayName?: string | null;
+  avatar?: string | null;
+  avatarColor?: string | null;
+  banner?: string | null;
+  bio?: string | null;
+}
+
 export interface FederationFriendshipPayload {
   from: FederationRelayParticipant;
   to: FederationRelayParticipant;
+  fromProfile?: FederationRelayProfileSnapshot;
+  toProfile?: FederationRelayProfileSnapshot;
   status?: 'pending' | 'accepted' | 'declined';
   createdAt: number;
 }