Expose `_fetchPackageManifest` within the `fast-npm-meta` client package

[kricsleo]

Clear and concise description of the problem

It can used to fetch the private packages metadata on the client side, allowing client-side data processing to match that of the server.
(Can be used by the node-modules-inspector)

Suggested solution

Move the _fetchPackageManifest to the fast-npm-meta package and export it.

fast-npm-meta/server/utils/fetch.ts

Line 16 in 4436925

async function _fetchPackageManifest(name: string, registry: string, userAgent: string): Promise<PackageManifest> {

Alternative

No response

Additional context

I'm willing to submit a PR for this. 🙌🏻

Validations

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