docs: mention nodejs_als compatibility flag

[max-lt]

Hello, I noticed some warning when running a cloudflare-adapter project with wrangler

npx wrangler pages dev .svelte-kit/cloudflare

▲ [WARNING] The package "node:async_hooks" wasn't found on the file system but is built into node.

  Your Worker may throw errors at runtime unless you enable the "nodejs_compat" compatibility flag.
  Refer to https://developers.cloudflare.com/workers/runtime-apis/nodejs/ for more details. Imported
  from:
   - .wrangler/tmp/pages-mQuBz9/bundledWorker-0.48410322524810456.mjs

Seems due to the missing AsyncLocalStorage API in workers by default.
I added some instructions to the doc to enable the required compatibility flag.

[changeset-bot]

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[svelte-docs-bot]

Preview: https://svelte-dev-git-preview-kit-13605-svelte.vercel.app/

[benmccann]

I think this may no longer be necessary because of #13607

[Conduitry]

I think this may no longer be necessary because of #13607

I would doubt it. The PR just removed the top-level await - the import of node:async_hooks is still present.

[eltigerchino]

Thanks for this. Can you update the Cloudflare Workers adapter docs too?