replace router/hydrate options with csr

[Rich-Harris]

Migration

export const router and export const hydrate where merged into export const csr. These two options really belong together, setting one to true and the other to false resulted in unexpected/buggy behavior. To migrate, remove the old options and replace them with the new option.

// +layout.js
- export const router = false;
- export const hydrate = false;
+ export const csr = false;

The following permutations are possible:

• old: router = true / hydrate = true -> new: csr = true (this is the default, so you probably don't need to set this)
• old: router = false / hydrate = false -> new: csr = false (no JS is loaded on the client)
• old: router = false / hydrate = true -> new: csr = true + set data-sveltekit-reload if you want native navigations
• old: router = true / hydrate = false -> new: csr = true (this was a buggy setting)

PR description

closes #6436

TODO:

• update create-svelte templates
• docs
• noisy error if a page has hydrate or router exports

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Latest commit: 977ad1e

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[MaximeMenotti]

Hi @Rich-Harris !
I use sveltekit in a micro-frontend like usage, injecting html and js generated by svelte-kit in another website.
I used router=false option to avoid sveltekit to interfere with the site but keep hydration to activate some js interaction.

I read in this PR that I should use this to keep same usage:

old: router = false / hydrate = true -> new: csr = true + set data-sveltekit-reload if you want native navigations

Unfortunately links like <a href="/" data-sveltekit-reload>Homepage</a> are still catch by sveltekit router.
Is there any other way or is it planned to allow to disable only the router for all links as it was the case before?
It was a very convenient feature for me, I hope I can find a solution.
Thanks and sorry to reopen this topic.

[lukaszpolowczyk]

@MaximeMenotti To me, this is simply a bug that needs to be reported separately.