fix(writing-skills): correct false 'only two fields' frontmatter claim (#882)

[arittr]

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Harness (e.g. Claude Code, Cursor)	Harness version	Model	Model version/ID

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[arittr]

This change is part of the following stack:

• docs(codex-tools): add named agent dispatch mapping for Codex #900
  • fix(writing-skills): correct false 'only two fields' frontmatter claim (#882) #903 ◀
    • fix(subagent-prompts): instruct subagents to read CLAUDE.md for project conventions #899
      • feat: Codex App worktree and sandbox compatibility #901
        • feat(codex): add Codex plugin marketplace artifacts and docs #904

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