Enable joining a room via identifier from another home server

Riot/Modules/DeepLink/MXRoomAliasResolution+Deeplink.swift

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+// 
+// Copyright 2022 New Vector Ltd
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+import Foundation
+import MatrixSDK
+
+@objc extension MXRoomAliasResolution {
+    
+    /// Deeplink fragment using a room identifier and a list of servers aware of this identifier
+    ///
+    /// For more details see
+    /// https://github.com/matrix-org/matrix-spec-proposals/blob/old_master/proposals/1704-matrix.to-permalinks.md
+    var deeplinkFragment: String? {
+        guard let roomId = roomId else {
+            MXLog.debug("[MXRoomAliasResolution]: Missing room identifier")
+            return nil
+        }
+        
+        guard let servers = servers, !servers.isEmpty else {
+            return roomId
+        }
+        
+        return roomId + "?via=" + servers.joined(separator: "&via=")
+    }
+}