Use the maxUploadSize in the media upload screen. (#4359)

* Fix a bug where some files sizes were sent as 0.

* Make FileManger.sizeForItem(at:) a UInt.

The docs specifically say that FileAttributeKey.size returns an unsigned long long so I have no idea why we were returning a Double here…

* Add the maxMediaUploadSize property on ClientProxy.

* Use the maxUploadSize to set a target video size and to show a file too big error.

* Refactor media upload parameter order.

ElementX/Sources/Screens/RoomDetailsEditScreen/View/RoomDetailsEditScreen.swift

@@ -155,6 +155,7 @@ struct RoomDetailsEditScreen_Previews: PreviewProvider, TestablePreview {
                                                   members: [.mockMeAdmin]))
         
         return RoomDetailsEditScreenViewModel(roomProxy: roomProxy,
+                                              clientProxy: ClientProxyMock(.init()),
                                               mediaProvider: MediaProviderMock(configuration: .init()),
                                               mediaUploadingPreprocessor: MediaUploadingPreprocessor(appSettings: ServiceLocator.shared.settings),
                                               userIndicatorController: UserIndicatorControllerMock.default)
@@ -166,6 +167,7 @@ struct RoomDetailsEditScreen_Previews: PreviewProvider, TestablePreview {
                                                   members: [.mockAlice]))
         
         return RoomDetailsEditScreenViewModel(roomProxy: roomProxy,
+                                              clientProxy: ClientProxyMock(.init()),
                                               mediaProvider: MediaProviderMock(configuration: .init()),
                                               mediaUploadingPreprocessor: MediaUploadingPreprocessor(appSettings: ServiceLocator.shared.settings),
                                               userIndicatorController: UserIndicatorControllerMock.default)