use isDM from the SDK to determine if a spaceRoom, a joinedRoom or a notificationItem are from a dm room.

NSE/Sources/NotificationItemProxy/NotificationItemProxy.swift

@@ -45,6 +45,10 @@ struct NotificationItemProxy: NotificationItemProxyProtocol {
         notificationItem.roomInfo.isDirect
     }
     
+    var isDM: Bool {
+        notificationItem.roomInfo.isDm
+    }
+    
     var isRoomPrivate: Bool {
         switch notificationItem.roomInfo.joinRule {
         case .invite, .knock, .restricted, .knockRestricted:
@@ -122,6 +126,10 @@ struct EmptyNotificationItemProxy: NotificationItemProxyProtocol {
         false
     }
     
+    var isDM: Bool {
+        false
+    }
+    
     var isRoomPrivate: Bool {
         false
     }

NSE/Sources/NotificationItemProxy/NotificationItemProxyProtocol.swift

@@ -35,6 +35,8 @@ protocol NotificationItemProxyProtocol {
     var isRoomDirect: Bool { get }
     
     var isRoomPrivate: Bool { get }
+    
+    var isDM: Bool { get }
 
     var isNoisy: Bool { get }
 
@@ -42,9 +44,3 @@ protocol NotificationItemProxyProtocol {
     
     var threadRootEventID: String? { get }
 }
-
-extension NotificationItemProxyProtocol {
-    var isDM: Bool {
-        isRoomDirect && roomJoinedMembers <= 2
-    }
-}