refactor(vercel): Build Output API v3

[JuanM04]

Changes

Now with Build Output API (v3)!

• Multiple deploy targets: edge, serverless and static.
• When building to serverless, the code isn't transpiled to CJS anymore.
• Meta: removed .output/ from gitignores

The users that migrate from v0.1 will have to do this:

1. Change the import inside astro.config.mjs:

   - import vercel from '@astrojs/vercel'
   + import vercel from '@astrojs/vercel/serverless'

2. Rename the ENABLE_FILE_SYSTEM_API environment variable to ENABLE_VC_BUILD, as Vercel changed it.
3. The output folder changed from .output to .vercel/output — you may need to update your .gitignore.

Testing

Docs

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Latest commit: 7a20b3b

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

This PR includes changesets to release 1 package

Name	Type
@astrojs/vercel	Minor

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[TooTallNate]

This is very cool! I'd love to test it out. Can you add testing instructions?

Also, if you have any questions and/or feedback regarding the new Build Output API, we'd love to hear from you over here.

Cheers!

[JuanM04]

@TooTallNate Thank you! I've been doing the following:

1. Clone this branch and run pnpm install && pnpm build
2. Clone one of the Astro starters (you can use pnpm create astro)
3. In the new project, add the local Vercel integration (pnpm add -D @astrojs/vercel@link:~/path/to/astro/packages/integrations/vercel)
4. Follow the instructions in the integration README
5. Deploy to Vercel with

   ENABLE_VC_BUILD=1 astro build
   vercel deploy --prebuilt

[TooTallNate]

Worked great for me 😄 https://my-astro-site-4nt1lu3gs-tootallnate.vercel.app/

[JuanM04]

Just as a note, this new version of the adapter fixes problems with Prisma: https://discord.com/channels/830184174198718474/845451724738265138/973950046531883048