provide access to request context via event.platform

[Rich-Harris]

closes #8706. If you have adapter-vercel installed, you'll get correct typings for event.platform automatically.

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[Rich-Harris]

Lint is failing because @vercel/edge and @types/node both define a global process var, but differently. Not sure how to fix

lint fails

[dummdidumm]

Ugh, that lint is from the @vercel/edge package, type checking fails in one of the d.ts files.

[dummdidumm]

My quick-fix-solution would be to copy over the needed type and remove the dependency on @vercel/edge

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

LGTM, this is awesome. I didn't know we could do this with Kit + Vercel.