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.

UnitTests/Sources/RoomDetailsEditScreenViewModelTests.swift

@@ -111,6 +111,7 @@ class RoomDetailsEditScreenViewModelTests: XCTestCase {
     private func setupViewModel(roomProxyConfiguration: JoinedRoomProxyMockConfiguration) {
         userIndicatorController = UserIndicatorControllerMock.default
         viewModel = .init(roomProxy: JoinedRoomProxyMock(roomProxyConfiguration),
+                          clientProxy: ClientProxyMock(.init()),
                           mediaProvider: MediaProviderMock(configuration: .init()),
                           mediaUploadingPreprocessor: MediaUploadingPreprocessor(appSettings: ServiceLocator.shared.settings),
                           userIndicatorController: userIndicatorController)