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/Services/Client/ClientProxy.swift

@@ -310,6 +310,17 @@ class ClientProxy: ClientProxyProtocol {
             }
         }
     }
+    
+    var maxMediaUploadSize: Result<UInt, ClientProxyError> {
+        get async {
+            do {
+                return try await .success(UInt(client.getMaxMediaUploadSize()))
+            } catch {
+                MXLog.error("Failed checking the max media upload size with error: \(error)")
+                return .failure(.sdkError(error))
+            }
+        }
+    }
 
     private(set) lazy var pusherNotificationClientIdentifier: String? = {
         // NOTE: The result is stored as part of the restoration token. Any changes