Uncaught (in promise) TypeError: n is null

[hexagon6]

Describe the bug

When changing an input in a bound variable of a story which is available under "Controls" UI, I get the following error in the console:

Uncaught (in promise) TypeError: n is null.

I figured out that in util.js there is a check for an object, and an access to $$.
If the value is null the typeof object test succeeds (since null is type of object) and access to $$ is tried, in which case the execution of the code halts on the aforementionent error, which freezes histoire any updates on inputs in the control panel.

I am providing a fix in a PR.

The solution would be to change the access to $$ like this:

old

    if (typeof value === 'object' && value.$$) continue

new

    if (typeof value === 'object' && value?.$$) continue

Reproduction

<script>
  /**
   * @type {{ Story: any; Variant: any; Text: any; }}
   */
  export let Hst

  let text = 'tag: text'
</script>

<Hst.Story title="todo.svelte" layout={{ type: 'grid', width: 500 }}>
  <Hst.Variant>
    <div>
      {text}
    </div>
    <svelte:fragment slot="controls">
      <Hst.Text bind:value={text} title="text" />
    </svelte:fragment>
  </Hst.Variant>
</Hst.Story>

System Info

latest ubuntu 22.04

Used Package Manager

npm

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