(core) custom widget appear as build-in widget

Summary: Added boilerplate code needed to create new wigets in "Add new" menu, that are wrapped around existing custom widgets. More details can be found here: https://grist.quip.com/larhAGRKyl6Z/Custom-widgets-in-Add-Widget-menu

Test Plan: nbowser tests added to verify if item in menu exits, if widget is rendered, and right side menu has widget selection and read access selection hided.

Reviewers: georgegevoian

Reviewed By: georgegevoian

Differential Revision: https://phab.getgrist.com/D3994

buildtools/fly-deploy.js

@@ -67,7 +67,7 @@ const appExists = (name) => runFetch(`flyctl status -a ${name}`).then(() => true
 const appCreate = (name) => runAction(`flyctl launch --auto-confirm --name ${name} -r ewr -o ${org} --vm-memory 1024`);
 const volCreate = (name, vol) => runAction(`flyctl volumes create ${vol} -s 1 -r ewr -y -a ${name}`);
 const volList = (name) => runFetch(`flyctl volumes list -a ${name} -j`).then(({stdout}) => JSON.parse(stdout));
-const appDeploy = (name, appRoot) => runAction(`flyctl deploy ${appRoot} --remote-only`, {shell: true, stdio: 'inherit'});
+const appDeploy = (name, appRoot) => runAction(`flyctl deploy ${appRoot} --remote-only --region=ewr`, {shell: true, stdio: 'inherit'});
 
 async function appDestroy(name) {
   await runAction(`flyctl apps destroy ${name} -y`);

buildtools/fly-template.toml

@@ -9,6 +9,7 @@ processes = []
   APP_HOME_URL="https://{APP_NAME}.fly.dev"
   APP_STATIC_URL="https://{APP_NAME}.fly.dev"
   ALLOWED_WEBHOOK_DOMAINS="webhook.site"
+  PERMITTED_CUSTOM_WIDGETS="calendar"
   GRIST_SINGLE_ORG="docs"
   PORT = "8080"
   FLY_DEPLOY_EXPIRATION = "{FLY_DEPLOY_EXPIRATION}"