docs: license engineering and bundled skills

[lemarier]

Change

Engineering has no repository license for its original code, documentation, templates, or skills. Add MIT OR Apache-2.0 using Origin89's existing license texts, and explain the scope in the README. Adapted skills retain their existing Apache-2.0 or MIT terms and upstream notices.

Declare each skill's license in its frontmatter and bundle both license texts with original skills so their terms travel through the existing folder-only installer. Add a repository check that verifies these copies match the root licenses and that adapted skills retain matching license declarations and notices.

Validation

• just check passed all 32 tests, including license consistency and installation of the complete canonical skill bundle in disposable consumers.
• git diff --check passed. Root license texts match the existing Origin89 source licenses byte for byte; upstream license and notice files are unchanged.
• No runtime or dependency changes; no Changeset needed.

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[chatgpt-codex-connector]

Codex Review Summary

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

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-09-11T17:05:32.215824Z	8cfb1c1	PR opened

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