chore: prepare v0.1.0-alpha.8 release

[chasechou007]

Summary

• bump package and lockfile version to 0.1.0-alpha.8
• freeze the standalone CLI distribution changes into the alpha.8 changelog section
• keep Unreleased open for later work

Verification

• Node 20, 22, and 24.18.0: 178/178 tests pass on each runtime
• installed-package smoke passes for the alpha.8 tarball
• npm pack dry-run contains 59 public consumer files
• npm audit reports 0 vulnerabilities
• OpenDomain validation passes for 26 documents with one known stale Candidate warning
• macOS arm64 alpha.8 SEA build, full binary smoke, codesign verification, and architecture check pass
• OpenSpec validation passes 10/10 items

Release boundary

This PR only prepares version metadata and release notes. It does not publish npm, create or push a tag, publish a GitHub Release, upload standalone release assets, or create the Homebrew Tap.

[chasechou007]

@codex review

[chatgpt-codex-connector]

Codex Review: Didn't find any major issues. Already looking forward to the next diff.

Reviewed commit: 56573ce47a

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

• Open a pull request for review
• Mark a draft as ready
• Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

Codex can also answer questions or update the PR. Try commenting "@codex address that feedback".