Audio Timeline Item support (#612)

* audio timeline item support

* improved the code to reduce cognitive complexity

* no need anymore for this swiftlint disabling of a rule

* pr comments

ElementX/Sources/Services/Timeline/TimelineItems/Items/Messages/AudioRoomTimelineItem.swift

@@ -0,0 +1,33 @@
+//
+// Copyright 2023 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
+
+struct AudioRoomTimelineItem: EventBasedTimelineItemProtocol, Identifiable, Hashable {
+    let id: String
+    let body: String
+    let timestamp: String
+    let groupState: TimelineItemGroupState
+    let isOutgoing: Bool
+    let isEditable: Bool
+    let sender: TimelineItemSender
+
+    let duration: UInt64
+    let source: MediaSourceProxy?
+    var cachedAudioURL: URL?
+
+    var properties = RoomTimelineItemProperties()
+}