Fixes #978 - Message forwarding support

* Add support for message forwarding

* Move the TimelineProvider within the RoomProxy to avoid it going out of sync and have it automatically register for timeline updates on init

* Implement single selection form button style for message forwarding

* Add searching and filter out the source room from the list

* Fixed emoji screen initial search bar height

* Add view models tests

* Add changelog

* Update strings

* Tweaks following code review

ElementX/Sources/Services/Timeline/TimelineController/MockRoomTimelineController.swift

@@ -68,7 +68,7 @@ class MockRoomTimelineController: RoomTimelineControllerProtocol {
     func debugInfo(for itemID: String) -> TimelineItemDebugInfo {
         .init(model: "Mock debug description", originalJSON: nil, latestEditJSON: nil)
     }
-    
+        
     func retryDecryption(for sessionID: String) async { }
     
     // MARK: - UI Test signalling

ElementX/Sources/Services/Timeline/TimelineController/RoomTimelineController.swift

@@ -43,17 +43,16 @@ class RoomTimelineController: RoomTimelineControllerProtocol {
     
     init(userId: String,
          roomProxy: RoomProxyProtocol,
-         timelineProvider: RoomTimelineProviderProtocol,
          timelineItemFactory: RoomTimelineItemFactoryProtocol,
          mediaProvider: MediaProviderProtocol) {
         self.userId = userId
-        self.timelineProvider = timelineProvider
+        self.roomProxy = roomProxy
+        timelineProvider = roomProxy.timelineProvider
         self.timelineItemFactory = timelineItemFactory
         self.mediaProvider = mediaProvider
-        self.roomProxy = roomProxy
         serialDispatchQueue = DispatchQueue(label: "io.element.elementx.roomtimelineprovider", qos: .utility)
         
-        self.timelineProvider
+        timelineProvider
             .itemsPublisher
             .receive(on: serialDispatchQueue)
             .sink { [weak self] _ in

ElementX/Sources/Services/Timeline/TimelineController/RoomTimelineControllerFactory.swift

@@ -23,7 +23,6 @@ struct RoomTimelineControllerFactory: RoomTimelineControllerFactoryProtocol {
                                      mediaProvider: MediaProviderProtocol) -> RoomTimelineControllerProtocol {
         RoomTimelineController(userId: userId,
                                roomProxy: roomProxy,
-                               timelineProvider: RoomTimelineProvider(roomProxy: roomProxy),
                                timelineItemFactory: timelineItemFactory,
                                mediaProvider: mediaProvider)
     }