Run server.init() for edge functions on Vercel

[SG60]

Required since #6179.

This should close #6308.

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🦋 Changeset detected

Latest commit: 2383041

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

This PR includes changesets to release 3 packages

Name	Type
@sveltejs/adapter-vercel	Patch
@sveltejs/adapter-netlify	Patch
@sveltejs/adapter-auto	Patch

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[benmccann]

I think we'll need to update the others as well. For example:

kit/packages/adapter-netlify/src/edge.js

Line 4 in 1e28edb

const server = new Server(manifest);

[Rich-Harris]

I think Netlify edge is the only one outstanding. Does 5ad9f8d look right based on https://docs.netlify.com/edge-functions/api/#deno-apis?