fix(ci): allow sharp/unrs-resolver build scripts via pnpm-workspace.yaml

[Origin173]

Checklist

• Changes have been tested locally and work as expected.
• All tests in workflows pass successfully.
• Documentation has been updated if necessary.
• Code formatting and commit messages align with the project's conventions.
• Comments have been added for any complex logic or functionality if possible.

This PR is a ..

• 🆕 New feature
• 🐞 Bug fix
• 🛠 Refactoring
• ⚡️ Performance improvement
• 🌐 Internationalization
• 📄 Documentation improvement
• 🎨 Code style optimization
• ❓ Other (Please specify below)

Related Issues

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• e.g. close #xxxx, fix #xxxx

The Build Artifacts workflow fails on pnpm install with ERR_PNPM_IGNORED_BUILDS.

Description

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Current pnpm versions (v10+) no longer honor the old only-built-dependencies key in .npmrc and fail pnpm install with ERR_PNPM_IGNORED_BUILDS for ignored native build scripts (sharp, unrs-resolver).

Add the replacement allowBuilds config in a new pnpm-workspace.yaml so pnpm install can run those build scripts again, and remove the dead .npmrc entries that no longer take effect.

Additional Context

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Verified locally with pnpm v11.22.0: pnpm import && pnpm install now succeeds and pnpm ignored-builds reports nothing ignored. Only build.yml uses pnpm; test.yml uses npm and is unaffected.