Add E2E test for restore-memory in custom jobs (gh-aw#44037)

[Copilot]

No E2E test existed for the restore-memory: frontmatter field on jobs.<id>, introduced in gh-aw#44037 to inject memory-restore steps into orchestrator jobs before the agent runs.

New test: test-copilot-restore-memory-custom-job

• test-copilot-restore-memory-custom-job.md — workflow_dispatch test with a jobs.setup custom job that declares restore-memory: {cache-memory: true}, a verification step, and jobs.agent depending on it via needs: [setup]:

jobs:
  setup:
    restore-memory:
      cache-memory: true
    steps:
      - name: Verify cache-memory restore step was injected
        run: echo "cache-memory restore step injection verified"
  agent:
    needs: [setup]

safe-outputs:
  create-issue:
    ...
    samples:
      - title: "restore-memory custom job smoke test"
        ...

• e2e.sh — registered in get_all_tests(), added *"restore-memory-custom-job" to the dispatch routing pattern and to the validate_issue_created inner case.
• README.md — added [ ] coverage entry.

Note on lockfile

restore-memory: in jobs.<id> is not yet recognized by the installed gh-aw (v0.81.6). The .lock.yml will be generated by the nightly CI when it compiles against a version that includes gh-aw#44037. Until then the test will be recorded in fails.txt as a compile-failed test — expected behavior per AGENTS.md.