build(plugin): add Python-free musl native artifacts

[kmbroai]

Summary

Prepare native OS primitives for Linux installations that use musl, so the TypeScript migration can preserve Alpine support.

Changes

• Distinguish GNU and musl Linux payloads using the Node diagnostic report header.
• Add native x64 and arm64 musl builds with pinned Rust and Node container images, offline compilation, and no Python dependency.
• Check ELF architecture and libc requirements, then test each unchanged binary on Node 20.0 and 22.13.

Testing

• On the rebased head: TypeScript compilation, SDK/MCP types, formatting, Rust formatting, Ruff, portable source checks, and all nine checker tests passed.
• The GNU native behavioral proof and musl ELF inspection passed locally.
• The original implementation is unchanged by the rebase. The earlier x64/arm64 musl proofs on Node 20 and 22 remain recorded in the PR history; fresh hosted jobs must verify this head's pinned containers.

Risk and rollout

Stacked on #795. This prepares build artifacts; product commands continue using their existing helpers. Universal package assembly and platform proofs remain required before TypeScript callers replace Python.

Public disclosure review

• No customer, partner, prospect, or user identities, data, or identifying details are included.
• No credentials, personal data, private source, scan findings, or nonpublic links or tickets are included.
• I reviewed the branch name, title, description, commits, changes, comments, logs, screenshots, attachments, and links for public disclosure.

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
🔒 Security Review	✅ Completed 2026-09-03T19:11:30.218946Z	e2cff42	New commits

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[mldangelo-oai]

I see the correction in 12303d2. The validator now attributes version requirements to their providing libraries, including the libgcc_s.so.1 compatibility case.

The current hosted arm64 musl job is still running. Holding approval until this head passes the ELF check, runs the same artifact through the Node 20 and 22 proofs, and uploads the verified artifact. The previous head stopped before the runtime proofs and upload; the new native-runner result will verify the fix.

[mldangelo-oai]

Reviewed the validator correction in 12303d2. The hosted arm64 musl job now passes ELF validation, runs the same artifact successfully on Node 20.0.0 and 22.13.0, and uploads the verified artifact. Both musl architectures and the current SDK CI run pass on this head. This clears my earlier approval hold.