Complete cross-platform native dependencies

[rgarcia]

Summary

• add every platform-specific Rolldown, Rollup, Sharp, and clipboard package to the lockfile at the existing exact dependency versions
• add a dependency-resolution-aware lockfile validator so Linux CI catches omitted native packages for other platforms
• run the validator before installs in CI and the Browser Loop release workflow

This fixes clean installs that passed on Linux but omitted the native bindings required to build on macOS ARM64.

Verification

• npx npm@11.17.0 ci --ignore-scripts --os=darwin --cpu=arm64 installs the expected macOS ARM64 Rolldown, Rollup, and Sharp packages
• negative validator check catches a deliberately removed @rolldown/binding-darwin-arm64 entry
• npx npm@11.17.0 ci
• npm run build --workspace @onkernel/browser-loop
• npm run typecheck --workspace @onkernel/browser-loop
• npm test --workspace @onkernel/browser-loop — 34 files, 429 tests

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