Support incoming audio only calls

libraries/matrix/api/src/main/kotlin/io/element/android/libraries/matrix/api/notification/NotificationData.kt

@@ -56,6 +56,7 @@ sealed interface NotificationContent {
         data class RtcNotification(
             val senderId: UserId,
             val type: RtcNotificationType,
+            val callIntent: CallIntent,
             val expirationTimestampMillis: Long
         ) : MessageLike
 
@@ -127,3 +128,8 @@ enum class RtcNotificationType {
     RING,
     NOTIFY
 }
+
+enum class CallIntent {
+    AUDIO,
+    VIDEO
+}