Room list: remove unused sorting ManualAlgorithm (#32724)

* chore: remove unused `ManualAlgorithm`

In the old room list ui, we can"t manually sort the rooms or the
sections. Neither in a menu or by drag and drop

* fix: add `undefined` to `tagRoom` signature since the code allows it

* test: add tests to `RoomListActions`

* chore: remuve unuseful comment

* refactor: remove unused ``newIndex

* doc: remove typing in tsdoc

apps/web/test/test-utils/test-utils.ts

@@ -356,6 +356,8 @@ export function createTestClient(): MatrixClient {
         kick: jest.fn(),
         ban: jest.fn(),
         sendTextMessage: jest.fn(),
+        deleteRoomTag: jest.fn().mockResolvedValue({}),
+        setRoomTag: jest.fn().mockResolvedValue({}),
     } as unknown as MatrixClient;
 
     client.reEmitter = new ReEmitter(client);