fix: remove dependency on copy-template-dir

[Lunnatica]

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Summary

Fixes #5724

We want to get rid of the deprecation warnings when running npm i -g netlify-cli.

This was caused by an outdated dependency in copy-template-dir, readdirp.

Since the package is no longer being maintained, this PR brings in the functionality of copy-template-dir so we can update readdirp to the latest version ourselves. A few changes to the copy-template-dir functionality have been done as part of this:

• Convert into ts
• Convert tests into vitest
• Get rid of unnecessary dependencies (e.g. graceful-fs)
• Upgrade dependencies that were brought in as part of the packages
• Remove unused cb argument

Testing

Running npm i in main (before changes):

Running npm i in the branch (with the changes):

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[github-actions]

📊 Benchmark results

Comparing with 85a74da

• Dependency count: 1,231 ⬇️ 9.02% decrease vs. 85a74da
• Package size: 295 MB ⬇️ 1.60% decrease vs. 85a74da
• Number of ts-expect-error directives: 997 (no change)

[TylerBarnes]

Dope! 🙌 🚀

[ben221199]

Nice