Propose Codex plugin marketplace structure

[breno12321]

Summary

This PR proposes a Codex plugin layer for the existing skills catalog.

It adds:

• a repo-local .agents/plugins/marketplace.json with 14 proposed plugin entries
• lightweight plugin wrapper directories under plugins/
• .codex-plugin/plugin.json metadata for each proposed plugin
• symlinked plugins/<plugin>/skills/<skill> entries back to the canonical skills/ catalog
• README documentation for the marketplace and plugin organization

The intent is to make the plugin boundaries reviewable without duplicating the skill content. If the release path requires self-contained plugin archives, the symlinks can be materialized into copied skill folders before ingestion validation or packaging.

Proposed Plugin Groups

• openai-codex-toolsmith
• openai-developers
• figma
• github
• openai-deploy
• vercel
• openai-web-automation
• openai-creative-media
• openai-documents-lab
• linear
• notion
• openai-app-frameworks
• openai-security
• sentry

Validation

• jq empty .agents/plugins/marketplace.json
• jq empty plugins/*/.codex-plugin/plugin.json
• custom Node structural validation for marketplace entries, manifest names, supported manifest fields, symlink resolution, and coverage of 43 unique skill names
• git diff --check

Note: the local bundled Python plugin validator could not run in this environment because python3 is missing PyYAML. The docs call out that symlinked wrappers should be materialized into copied skill folders before validating a self-contained plugin archive, especially for skills with agent icon assets.

AI Involvement

• Tool(s): Codex / GPT-5
• Involvement level: AI-generated
• What AI produced: Proposed the plugin grouping, added the .agents marketplace metadata, created plugin wrapper manifests and symlink layout, documented the structure and validation caveats.