feat: Convert all app files to JS

packages/backend/src/apps/todoist/auth/verify-credentials.js

@@ -0,0 +1,14 @@
+const verifyCredentials = async ($) => {
+  const { data } = await $.http.post(`${$.app.baseUrl}/oauth/access_token`, {
+    client_id: $.auth.data.clientId,
+    client_secret: $.auth.data.clientSecret,
+    code: $.auth.data.code,
+  });
+
+  await $.auth.set({
+    tokenType: data.token_type,
+    accessToken: data.access_token,
+  });
+};
+
+export default verifyCredentials;