test: add golden generator coverage

[brendanjryan]

Motivation

Generated marketplace artifacts are public interfaces. Exact-output tests make metadata changes reviewable and prevent silent cross-platform drift.

Summary

• Add golden files for every generated manifest, extension manifest, and release plugin name
• Make generation functions independently testable
• Add a deterministic golden refresh command
• Detect and remove orphaned generated manifests
• Prevent internal launch-state language from returning to public documentation

Key design considerations

• Keep golden updates explicit and reviewer-controlled
• Verify copied skills and licenses byte-for-byte without duplicating them in fixtures
• Limit pruning to known generated manifest paths

[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 2026-09-03T19:47:01.222272Z	4d48dcd	PR opened

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