CSRF failure doesn't pass ActionData to enhanced form callback nor supplies form.error.

Describe the bug

I'm noticing odd behaviour when CSRF fails - when the form is submitted no error message is given.

I see the server is returning code 403 with {message: "Cross-site POST form submissions are forbidden"} which doesn't comply with ActionResult type in the enhance callback function and form.error isn't updated.

{#if form?.success}
	<p class="success">Success</p>
{:else if form?.error}
	<p class="error">{form.error}</p>
{/if}

use:enhance={async ({ formData }) => {
	return async ({ result, update }) => {
		await update();
	};
}}

Is this intended?

How can one catch the 403 error in the callback and/or display a custom message upon CSRF failure?

Right now I can do the following, but cannot force an error message into form.error:

if (result?.type !== 'success' && result?.message) {
	console.log(result.message);
}

Expected format of the CSRF failure would probably be:

{ type: 'error'; status: 403; error: "Cross-site POST form submissions are forbidden"}

Reproduction

https://stackblitz.com/edit/sveltejs-kit-template-default-f1rj2m?file=src%2Froutes%2F%2Bpage.svelte

Logs

No response

System Info

System:
    OS: Linux 5.15 AlmaLinux 8.8 (Sapphire Caracal)
    CPU: (2) x64 Intel(R) Xeon(R) CPU E3-1240 v5 @ 3.50GHz
    Memory: 852.82 MB / 2.00 GB
    Container: Yes
    Shell: 4.4.20 - /bin/bash
  Binaries:
    Node: 16.14.0 - /usr/bin/node
    npm: 8.3.1 - /usr/bin/npm
  npmPackages:
    @sveltejs/adapter-node: ^1.3.1 => 1.3.1 
    @sveltejs/kit: ^1.22.3 => 1.22.3 
    svelte: ^4.1.1 => 4.1.1 
    vite: ^4.4.7 => 4.4.7

Severity

serious, but I can work around it

Additional Information

No response

Start with the reproduction in src/routes/+page.svelte and inspect the use:enhance callback's handling of the 403 CSRF response. Compare that result with the ActionResult and form.error behavior described in the issue. Done means a CSRF failure is represented consistently for the callback and can display an error through the form state.