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.

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[teemingc]

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

[benmccann]

@eltigerchino I just fixed the merge conflict on this one. Do you still think we should update the Cloudflare Workers docs since the two adapters have been merged? I see there's also a Cloudflare Workers section in the Cloudflare Adapter doc. You're more familiar with Cloudflare, so I thought you might have a good suggestion of what would need to be updated

[teemingc]

Thank you!

Do you still think we should update the Cloudflare Workers docs since the two adapters have been merged?

We could because it should be the exact same as the Cloudflare docs so we can just copy and paste it.

I see there's also a Cloudflare Workers section in the Cloudflare Adapter doc. You're more familiar with Cloudflare, so I thought you might have a good suggestion of what would need to be updated

I think we might want to suggest having the compatibility flag added in the user's Wrangler config file over using the dashboard or CLI option so that it's always set up on deployment/dev. We might also want to explain it's only needed if using getRequestEvent asynchronously.

[Rich-Harris]

opened #14189 as a possible alternative, basically forcing everyone to add this flag to avoid the warning

[ghostdevv]

I think we should consider merging this, at least as a stop-gap, as part of addressing #15056. Will contribute to reducing confusion/friction in the meantime.

[elliott-with-the-longest-name-on-github]

I'm going to go ahead and merge this as it's helpful in the near term. If someone wants to put the work in on the associated PR, or if there's a better fix we can arrive at, there's nothing stopping us from reverting this when the better fix is implemented.