fix(executor): correct cmux review-surface attach in /launch (v1.3.2)

[memorysaver]

Fixes how aep-launch / aep-executor attach a cmux review surface. Three bugs, reported and verified live from a downstream (looplia) session.

Bugs fixed

1. Detection gated on $CMUX_SOCKET → a host where the cmux CLI is reachable but $CMUX_SOCKET is unset (Claude Code inside a cmux-managed tmux session) wrongly fell back to headless B2. Detection now keys on cmux CLI reachable AND a target pane resolves (cmux tree ◀ here / $CMUX_PANE_ID), independent of $CMUX_SOCKET.
2. Wrong tab placement → the bare cmux new-surface defaulted to an unset $CMUX_WORKSPACE_ID. Now /launch resolves the orchestrator's own pane from cmux tree and opens a sibling tab via new-surface --workspace <ws> --pane <pane> --focus true. cmux new-workspace (separate top-level workspace) is kept out of the launch path.
3. Bootstrap lost → an attached cmux surface focuses the tmux composer and blocks external send-keys, so the bootstrap couldn't land. Reordered: spawn tmux → wait ready → send bootstrap via tmux send-keys → then attach the cmux tab.

Files

• skills/agentic-development-workflow/launch/SKILL.md — Spawn (defer cmux), Send Bootstrap (always tmux), new "Attach the cmux Review Tab (B1)" step
• skills/patterns/executor/references/backends.md — detection, B1 recipe, present(), fallback ladder
• skills/patterns/executor/SKILL.md — detection summary
• marketplace.json 1.3.1 → 1.3.2 + CHANGELOG.md [1.3.2]

Acceptance

• cmux running but $CMUX_SOCKET unset → review tab opens in the orchestrator's current cmux project pane (beside its own tab), not a new top-level workspace and not silent headless tmux.
• The build agent receives its bootstrap (sent before the surface attached).
• No cmux new-workspace in the launch path.

Note: the cmux verbs were verified live in the reporting session; the integration here should be confirmed on an actual cmux host before relying on it.

🤖 Generated with Claude Code