fix: publish to npm registry directly instead of Yarn proxy

[masnwilliams]

Summary

• Adds registry: "https://registry.npmjs.org" to publishConfig in package.json
• Fixes yarn publish failing with "https://registry.yarnpkg.com/@onkernel%2fsdk: Not found" because Yarn's registry proxy is failing for scoped package publishes
• No code or publish script changes were made between v0.30.0 (which worked) and v0.31.1 (which failed) — this is an external Yarn registry issue

Test plan

• Re-run the Publish NPM workflow after merging

Made with Cursor

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Note

Low Risk
Single metadata change affecting publish destination only; no runtime code changes, but it can impact release/publish behavior.

Overview
For npm publishing, package.json now pins publishConfig.registry to https://registry.npmjs.org (keeping access: "public") so yarn publish targets the npm registry directly instead of Yarn’s proxy.

^{Written by Cursor Bugbot for commit 52a9c5d. This will update automatically on new commits. Configure here.}