Fixes #2320 - Implement support for (un)marking rooms as favourite from the room list and room detail screens

ElementX/Sources/Application/AppSettings.swift

@@ -49,6 +49,7 @@ final class AppSettings {
         case mentionsBadgeEnabled
         case roomListFiltersEnabled
         case markAsUnreadEnabled
+        case markAsFavouriteEnabled
     }
     
     private static var suiteName: String = InfoPlistReader.main.appGroupIdentifier
@@ -285,6 +286,9 @@ final class AppSettings {
     @UserPreference(key: UserDefaultsKeys.markAsUnreadEnabled, defaultValue: false, storageType: .userDefaults(store))
     var markAsUnreadEnabled
     
+    @UserPreference(key: UserDefaultsKeys.markAsFavouriteEnabled, defaultValue: false, storageType: .userDefaults(store))
+    var markAsFavouriteEnabled
+    
     #endif
     
     // MARK: - Shared