kit feat: add %sveltekit.version% placeholder for template interpolation

Allow app.html to interpolate the version string passed to kit.version.name in svelte.config.js. This makes it easier for static <head> includes for third-party scripts to be passed the current app version, e.g.

<script>
  GenericAnalytics.init({
    token: "abc123",
    application: "web",
    version: "%sveltekit.version%",
  });
</script>

This is nice ergonomic improvement, but there are several available workarounds:

set a variable using a globally included %sveltekit.head%
duplicate the version string to an env variable and use %sveltekit.env.PUBLIC_VERSION%
do your own pre-templating of app.html in hooks.server

This PR resolves https://github.com/sveltejs/kit/issues/12130.

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Apr 16 '24 20:04 potch

🦋 Changeset detected

Latest commit: eda91c8d43559d0f7aef2de6379ba61e9a188ead

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

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@sveltejs/kit	Minor

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Apr 16 '24 20:04 changeset-bot[bot]

If we did do this it would need to be added to the documentation. I'm not sure if needs to be in the playground though

The main question I have is whether we should add this vs having folks use the layout: https://github.com/sveltejs/kit/issues/12130#issuecomment-2059894722

Jun 19 '24 19:06 benmccann