title: Add a watcher for form fields
body: <p>I'm using Laravel Nova, and I want to make "Save" button(on the Update view)  unavailable while all required fields are empty.
  Here's the part of the code of the "Update.vue" file that creates my form fields:</p>
  
  <pre><code>&lt;div v-for="field in fields"&gt;
   &lt;component
      @file-deleted="updateLastRetrievedAtTimestamp"
      :is="'form-' + field.component"
      :errors="validationErrors"
      :resource-id="resourceId"
      :resource-name="resourceName"
      :field="field"
   /&gt;&lt;/div&gt;
  </code></pre>
  
  <p><code>Fields</code> array fills with the data from backend.</p>
  
  <p>So I can see this structure in the Vue dev tool. And when I change the input value it changes <code>value</code> of <code>&lt;form-text-field&gt;</code>, but I don't see this changes anywhere in my <code>Update</code> component.</p>
  
  <p><a href="https://i.stack.imgur.com/6nBqB.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/6nBqB.png" alt="enter image description here"></a></p>
  
  <p>So my question is - How I can get changes of my input fields dynamically? </p>