Use when user invokes /harness-sync or wants to sync AI tool configurations across any of the 8 supported targets (Claude Code, Cursor, GitHub Copilot, Codex, OpenCode, Windsurf, Gemini CLI, Junie). Inventories installed skills, instruction blocks, and MCP configs on all detected platforms, reports divergence, and lets the user push or pull changes. Push path reuses harness-compile logic. Pull path updates harness.yaml and recompiles. Never overwrites without explicit confirmation.
