feat(session): snapshot getters for IgnoredUsersManager + GroupInformationManager

Extends the v2.1.0 React-friendly snapshot pattern (originally on
SessionDataManager / RoomSessionManager) to two more session-state
holders the React client reads frequently:

- IgnoredUsersManager.getIgnoredUsersSnapshot(): ReadonlyArray<string>
- GroupInformationManager.getGroupBadgesSnapshot(): ReadonlyMap<number, string>

Both follow the same shape: lazy-frozen snapshot, cached until the
underlying state mutates, then invalidated and a dispatched event lets
the React client rebuild via useSyncExternalStore.

Two new NitroEventType members carry the invalidation signal:
- IGNORED_USERS_UPDATED — dispatched by IgnoredUsersManager whenever
  the list changes (initial load, add, remove, queue-truncate case 2).
- GROUP_BADGES_UPDATED — dispatched by GroupInformationManager only
  when the incoming HabboGroupBadges payload contains at least one
  new or changed mapping (no-op refresh stays quiet).

This lets the user-info popup, profile page, friend/guild filtering,
and any other consumer share a single read through useSyncExternalStore
instead of each subscribing to the underlying message events
independently.

API additions are interface-respecting and backwards-compatible — the
existing `isIgnored(name)` / `getGroupBadge(groupId)` accessors stay
untouched.

packages/events/src/NitroEventType.ts

@@ -19,4 +19,6 @@ export class NitroEventType
     public static readonly FURNITURE_DATA_LOADED = 'FURNITURE_DATA_LOADED';
     public static readonly SESSION_DATA_UPDATED = 'SESSION_DATA_UPDATED';
     public static readonly ROOM_SESSION_UPDATED = 'ROOM_SESSION_UPDATED';
+    public static readonly IGNORED_USERS_UPDATED = 'IGNORED_USERS_UPDATED';
+    public static readonly GROUP_BADGES_UPDATED = 'GROUP_BADGES_UPDATED';
 }