Create Notification normalizer

app/soapbox/normalizers/notification.ts

@@ -0,0 +1,20 @@
+import {
+  Map as ImmutableMap,
+  Record as ImmutableRecord,
+} from 'immutable';
+
+// https://docs.joinmastodon.org/entities/notification/
+const NotificationRecord = ImmutableRecord({
+  account: null,
+  chat_message: null, // pleroma:chat_mention
+  created_at: new Date(),
+  emoji: null, // pleroma:emoji_reaction
+  id: '',
+  status: null,
+  target: null, // move
+  type: '',
+});
+
+export const normalizeNotification = (notification: ImmutableMap<string, any>) => {
+  return NotificationRecord(notification);
+};