Add availableMediaTypes bitmask to receiver selector open method

app/NativeMacReceiverSelector/models/InitData.swift

@@ -1,6 +1,7 @@
 struct InitData : Codable {
     let receivers: [Receiver]
     let defaultMediaType: MediaType
+    let availableMediaTypes: Int
 
     let i18n_extensionName: String
     let i18n_castButtonTitle: String

app/NativeMacReceiverSelector/models/MediaType.swift

@@ -1,3 +1,8 @@
-enum MediaType : Int, Codable {
-    case app, tab, screen
+import Foundation
+
+
+enum MediaType: Int, Codable {
+    case app = 1
+    case tab = 2
+    case screen = 4
 }