Fix: Correct action path in Svelte scaffold new templates

[alec-c4]

The Svelte scaffold generator created broken new.svelte files that caused runtime errors when creating new records. This issue affected all 4 Svelte scaffold templates (with/without Tailwind, with/without TypeScript) but NOT React or Vue

Root cause: All Svelte new.*.svelte.tt templates incorrectly used <%= js_resource_path %> for the Form action, which expands to #{route_url}/${#{singular_table_name}.id}. For a new record, post.id is undefined, resulting in an invalid URL like /posts/undefined and causing a TypeError.

Additionally, one template (inertia_tw_templates/scaffold/templates/svelte/new.svelte.tt) included an invalid onSubmit={handleSubmit} prop that referenced an undefined function, causing a ReferenceError.

Before (broken):

  <Form
    {post}
    submitText="Create Post"
    onSubmit={handleSubmit}
    action="/posts/${post.id}"  <!-- post.id is undefined -->
    method="post"
  />

After (fixed):

  <Form
    {post}
    submitText="Create Post"
    action="/posts"  <!-- Correct collection path -->
    method="post"
  />

[alec-c4]

@skryukov there was a typo in your commit a0e7129