Suggested test: copilot/on-cooldown-gating

## Motivation

github/gh-aw#56998 — Adds a configurable `on.cooldown` gating: workflows check run history via `actions: read` and skip agent execution if a prior successful/failed run of the `agent` job occurred within the cooldown window (min 5 minutes, literal Go duration only, no GitHub Actions expressions allowed).

## Proposed test

- **Workflow file**: `test-copilot-cooldown.md`
- **Trigger**: `workflow_dispatch`
- **Engine**: copilot
- **Safe output**: `create-issue` (minimal payload to confirm agent ran)
- **Variant**: standard

## Minimal test prompt sketch

Compile a workflow with `on: { workflow_dispatch:, cooldown: 5m }` and a trivial prompt that creates an issue. Dispatch it twice in quick succession and assert the second run's agent job is skipped (no new issue), while a run after the cooldown window proceeds normally.

## New fixtures or secrets needed

None — needs `actions: read` permission, already available.

## Notes

Cooldown enforces a 5-minute minimum, so exercising "gated" vs "not gated" behavior needs either a short sleep/second dispatch inside the same test run or accepting a longer test duration. Feasibility of a fast, deterministic assertion (e.g., checking the second run's job conclusion/skip reason via `gh run view`) should be confirmed before writing the `.md` — filing as an issue for triage rather than a ready-made source file.

> Generated by [🔍 Suggest New E2E Tests](https://github.com/githubnext/gh-aw-test/actions/runs/33374036874) · copilot · auto · 28.1 AIC · ⌖ 8.6 AIC · ⊞ 8.8K · [◷](https://github.com/search?q=repo%3Agithubnext%2Fgh-aw-test+is%3Aissue+%22gh-aw-workflow-call-id%3A+githubnext%2Fgh-aw-test%2Fsuggest-new-e2e-tests%22&type=issues)

Start by reviewing the proposed `test-copilot-cooldown.md` workflow and how existing tests dispatch workflows. Confirm whether `gh run view` can deterministically verify the second run's skipped agent job without waiting five minutes. Done means the first dispatch creates an issue, a quick second dispatch is gated, and a later dispatch proceeds normally.

Written by the indexing model from the issue text.