Decide what to do with Claude Cowork, MCP, and vouch workflows in the Codex fork

[ethanolivertroy]

Context

The source repo includes adjacent workflows that may or may not belong in the Codex fork:

• docs/CLAUDE-COWORK.md
• .mcp.json with Linear MCP configuration
• Vouch workflows under .github/workflows/vouch-*.yml
• Contributor docs that reference the source repo and vouch process

These are not all wrong, but they need explicit decisions for the fork.

Tasks

• Decide whether Claude Cowork docs stay as legacy/source compatibility, move to an archive, or are replaced by Codex docs.
• Verify whether Codex app supports or should use the included .mcp.json pattern.
• Test or document vouch workflow behavior in the forked repo.
• Update docs/CONTRIBUTING.md, GOVERNANCE.md, and security docs for the Codex repo namespace.
• Ensure contributor protections still work without blocking legitimate Codex migration PRs.

Acceptance Criteria

• The repo clearly states which non-Codex workflows are retained, deprecated, or unsupported.
• Governance and contributor automation references this fork, not only the source repository.