refactor: code clean up (#3681)

* refactor: code clean up
Move types from App.tsx to types.ts
Move excalidrawPackage.test.tsx inside src/tests/package

* import type

src/excalidraw-app/collab/CollabWrapper.tsx

@@ -1,6 +1,6 @@
 import throttle from "lodash.throttle";
 import React, { PureComponent } from "react";
-import { ExcalidrawImperativeAPI } from "../../components/App";
+import { ExcalidrawImperativeAPI } from "../../types";
 import { ErrorDialog } from "../../components/ErrorDialog";
 import { APP_NAME, ENV, EVENT } from "../../constants";
 import { ImportedDataState } from "../../data/types";