breaking: throw redirects from remote functions

[Rich-Harris]

WIP. Addresses #16328 (comment). This will fix and simplify stuff, but it's also a breaking change for anyone using experimental.remoteFunctions.

It depends on changes to Svelte itself which I'm currently working on. Specifically, we need state changes that occur in transformError to apply before boundaries are activated, and for errors in effects that are destroyed as a result of those state changes to be disregarded.

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[pkg-svelte-dev]

Install the latest version of @sveltejs/kit from 75cef1f:

pnpm add https://pkg.svelte.dev/@sveltejs/kit/c/75cef1fc8c5a7d72a6e139cd3c8513a17d6af2d4

Open in pkg.svelte.dev: https://pkg.svelte.dev/repos/kit/pr/16330

[changeset-bot]

🦋 Changeset detected

Latest commit: 75cef1f

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

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@sveltejs/kit	Minor

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[svelte-docs-bot]

Preview: https://svelte-dev-git-preview-kit-16330-svelte.vercel.app/

[Nic-Polumeyv]

See: #16275 (comment)