[Sprint 21] Sync Squad coordinator and workflow templates

[mpaulosky]

Summary\nPublish pending Squad framework updates currently staged on dev, including coordinator guidance, skills, and workflow template updates.\n\n## Scope\n- Commit staged .github/.squad/.mcp related updates\n- Push to issue branch on origin\n\n## Why\nPreserve and review the current Squad upgrade changes via normal branch workflow.

[github-actions]

📋 Assigned to Boromir (DevOps / Infra)

Issue: #457 — [Sprint 21] Sync Squad coordinator and workflow templates

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Boromir, work on issue #457

[mpaulosky]

Closed by #458 (merged into dev).