breaking: Move cloudflare bindings from platform to cloudflare:workers

[ottomated]

Breaking #16705 into smaller pieces; this is the first step of making the dev environment closer to the workerd runtime. Instead of accessing Cloudflare bindings on platform.env, you would do the following:

import { env } from 'cloudflare:workers';

export function GET({ request }) {
  const value = await env.KV.get('key'); // instead of platform.env
  const userCountry = request.cf.country; // instead of platform.cf
  const cache = caches.open('name'); // instead of platform.caches
}

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Install the latest version of @sveltejs/kit from 1f442d6:

pnpm add https://pkg.svelte.dev/@sveltejs/kit/c/1f442d6cb9c9939a9a95d3df5c696b7c67585e26

Open in pkg.svelte.dev: https://pkg.svelte.dev/repos/kit/pr/16754

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🦋 Changeset detected

Latest commit: 1f442d6

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

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Name	Type
@sveltejs/adapter-cloudflare	Major

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[svelte-docs-bot]

Preview: https://svelte-dev-git-preview-kit-16754-svelte.vercel.app/

[teemingc]

We should definitely open a separate PR to showcase how to hook up the output of wrangler types to type the entire env object so that the user doesn't use @cloudflare/workers-types or have to spell out the bindings here

[ottomated]

I did mention that below, this section is just to get the docs types correct

[teemingc]

Yeah, what I meant was we should make that change independant of this PR. It's a good change to have and will make this one smaller