[FIX] Use the 'browser' platform setting for esbuild for Vercel Edge Functions

[SG60]

This should use the same esbuild platform setting as the Cloudflare adapter, as Vercel Edge Functions are based on Cloudflare Workers. I discovered this issue while using the Supabase JS client.

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Latest commit: a1b9d87

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This PR includes changesets to release 2 packages

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

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