feat: introduce hightlighted room getter

- adds `Room.isUnreadOrInvited` extending `Room.isUnread` to invited rooms

This is some high-level abstraction simplifying computation of unread
room badges / notifications.

Related: https://gitlab.com/groups/famedly/company/-/epics/28

Signed-off-by: TheOneWithTheBraid <the-one@with-the-braid.cf>

lib/src/room.dart

@@ -530,6 +530,10 @@ class Room {
   /// in muted rooms, use [hasNewMessages].
   bool get isUnread => notificationCount > 0 || markedUnread;
 
+  /// Returns true if this room is to be marked as unread. This extends
+  /// [isUnread] to rooms with [Membership.invite].
+  bool get isUnreadOrInvited => isUnread || membership == Membership.invite;
+
   @Deprecated('Use waitForRoomInSync() instead')
   Future<SyncUpdate> get waitForSync => waitForRoomInSync();
 
@@ -1689,6 +1693,7 @@ class Room {
 
   bool get canCreateGroupCall =>
       canChangeStateEvent('org.matrix.msc3401.call') && groupCallsEnabled;
+
   bool get canJoinGroupCall =>
       canChangeStateEvent('org.matrix.msc3401.call.member') &&
       groupCallsEnabled;

test/room_test.dart

@@ -189,7 +189,8 @@ void main() {
           stateKey: '',
         ),
       );
-      expect(room.hasNewMessages, true);
+      expect(room.hasNewMessages, isTrue);
+      expect(room.isUnreadOrInvited, isTrue);
       expect(room.lastEvent?.body, 'cd');
       room.setState(
         Event(