docs: Update the linked playgrounds in the snippet docs

[JR-G]

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For #14114

I've updated the playground links to make the table a bit nicer on the eyes in dark mode:

Before	After

There's also a link further down the page:

Any content inside the component tags that is not a snippet declaration implicitly becomes part of the children snippet (demo):

that appears to be pointing to the wrong example.

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[github-actions]

Playground

pnpm add https://pkg.pr.new/svelte@14676

[Conduitry]

Thanks, but this is for the old svelte-5-preview site, which no longer exists. These should be edited in the file linked to by the 'edit this page' at the bottom of https://svelte.dev/docs/svelte/snippet

[Rich-Harris]

preview: https://svelte-dev-git-preview-svelte-14676-svelte.vercel.app/

this is an automated message

[JR-G]

Thanks, but this is for the old svelte-5-preview site, which no longer exists. These should be edited in the file linked to by the 'edit this page' at the bottom of https://svelte.dev/docs/svelte/snippet

@Conduitry rectified

[Rich-Harris]

Thank you! Tweaked slightly to use system colors, the bright background is jarring in dark mode