add phone type placeholder

app/javascript/application.js

@@ -75,6 +75,7 @@ window.customElements.define('template-builder', class extends HTMLElement {
     this.app = createApp(TemplateBuilder, {
       template: reactive(JSON.parse(this.dataset.template)),
       backgroundColor: '#faf7f5',
+      withPhone: this.dataset.withPhone === 'true',
       isDirectUpload: this.dataset.isDirectUpload === 'true'
     })