AP Undo Announce (#5400)

* AP Undo Announce

* Use activity id

src/remote/activitypub/kernel/undo/announce.ts

@@ -0,0 +1,16 @@
+import { Notes } from '../../../../models';
+import { IRemoteUser } from '../../../../models/entities/user';
+import { IAnnounce, getApId } from '../../type';
+import deleteNote from '../../../../services/note/delete';
+
+export const undoAnnounce = async (actor: IRemoteUser, activity: IAnnounce): Promise<void> => {
+	const uri = getApId(activity);
+
+	const note = await Notes.findOne({
+		uri
+	});
+
+	if (!note) return;
+
+	await deleteNote(actor, note);
+};