feat: add `bundleStrategy: 'inline'

[Rich-Harris]

This is something of an experiment. The idea is that, building on top of #13173, it should be possible to bundle a SvelteKit app right into the HTML, so that you can literally just double-click an app.html file.

Most apps shouldn't be built this way! But there are certain use cases where it's kinda fun — imagine being able to build a game and literally email it to your friends, without needing to host it somewhere.

This PR has no tests yet and there are probably some things that don't work correctly. It may turn out that there are insurmountable technical challenges, I don't know yet.

If this works, it should basically close #907, though there may be some wrinkles around .html extensions depending on how the app is consumed.

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[Rich-Harris]

preview: https://svelte-dev-git-preview-kit-13193-svelte.vercel.app/

this is an automated message

[tizu69]

what is the play for routes? Does each route get its own bundled code, or is there one bundled codebase that is then just put into all pages? I was gonna ask about dynamic routes, but I'm assuming they aren't possible with this either way I'm assuming.

[Rich-Harris]

One bundle. It doesn't impose any restrictions on what kind of app you can build, just means that the bundle size is correlated to app size

[dummdidumm]

This doesn't seem to work for me at all. It may work by chance if you prerender the entry point, but if you don't, or navigate anywhere in the app, then everything breaks:

• protocol is file:, so pathname contains the whole path to the file on disk (e.g. on windows something like /C:/foo/bar/index.html. That breaks all matching logic
• it's not self-contained yet: it contains __vitePreload entries, one for each node (page/layout/etc), which all try to load a JS bundle. That fails completely
• when something fails it tries to request version.json to see if a new version is available, this fails

[Rich-Harris]

It doesn't work after merging the hash based routing PR — I have some changes locally, and a test app that works perfectly