feat: allow the measured Windows Codex queue release

[fujibee]

Summary

Permit new Windows queue operations only when a native codex.exe resolves and that executable reports codex-cli 0.157.0. This release has measured evidence that native queue creates no descendants and that its notice reaches a logged-in live conversation. Missing executables, unreadable version output, and every unlisted version remain blocked with a reason. The version probe has a two-second timeout and bounded output. Queue launches use the resolved native path directly, including the measured npm global installation layout, rather than its JavaScript or shell shim.

Apply the same gate while reconciling pending Windows operations, preserving confirmation and expiry observations even when a changed or unavailable executable blocks new delivery.

Add an anonymized, measured Windows response_item fixture from 2026-10-01, preserving field types and positions, including metadata.client_authored=false and metadata.user_input_order. One regression verifies that the fixture's user input nonce is observed as present.

Validation

• node --test tests/agmsgd_codex_queue.test.mjs: 9/9 PASS.
• bats tests/test_agmsgd_codex_queue.bats: 1/1 PASS (runs the Node support suite).
• git diff --check: PASS.
• Tests cover executable resolution, the measured npm layout, unlisted and unreadable versions, native executable forwarding, pending-to-confirmed Windows delivery, and preventing duplicate nudges for a confirmed snapshot.

Validation ran on macOS with disposable profiles and mocked native version/queue processes. It did not launch a live Windows service or modify a user queue. The measured rollout fixture and native path layout were supplied from the existing Windows live-delivery measurement.

Targets integration/agmsgd-beta. Merge is handled by the integration coordinator.