[Svelte] Filter out deprecated types for event handlers on:* from extending types from svelte/element

[xeho91]

Is your feature request related to a problem? Please describe.

The automatic argTypes extraction for Svelte since v8.4 is 🔥 🔥 🔥 🩷 🧡 !

There's one gotcha that makes it a little too verbose and annoying. And this is for Svelte v5.

Is it a common practice to extend types from svelte/elements where you can get types for event handlers.

Example component code:

<!-- Button.svelte -->
<script lang="ts">
  import type { HTMLButtonAttributes } from "svelte/elements";
  
  interface Props extends HTMLButtonAttributes {}
  let { children, ...rest }: Props = $props();
</script>

<button {...rest}>
  {@render children?.()}
</button>

Writing stories for this one example component will create arg table like this:

As you can notice, there are some duplicates. Because svelte/elements provides deprecated event handlers types for v4 - for the backwards compatibility support.
In Svelte v5 there's been a breaking change by removing the : from event handlers.
So for example on:click becomes onclick.

Describe the solution you'd like

We can improve the DX by filtering out those deprecated event handlers starting with on:*.

Use detection if Svelte v5 is being used and filter out argType names that start with on:.

Describe alternatives you've considered

No response

Are you able to assist to bring the feature to reality?

yes, I can

Additional context

No response