[self-care:open-source-failures] Fix target authority declaration blocking live-mode maintenance workflows

A shared target-authority precompute failure is blocking four live-mode workflows in `githubnext/gh-aw-cao`, with 19 recurrences in the bounded seven-day snapshot.

**Action:** A CAO maintainer should fix the target authority declaration on the protected default branch for the affected packages and re-run one workflow from each affected family; accept when `aw-failures-investigator`, `aw-maintenance-compiler-security`, `aw-maintenance-upgrade`, and `dependabot-release-train-updater` all pass precompute without the same target-authority error.

Agent prompt

Inspect `.github/workflows/cao.json` on the default branch and update the target-authority declaration so live-mode package authority is valid for the affected workflows. Keep the change minimal, preserve fail-closed behavior, and verify the schema/version and package authority entries required by CAO precompute. After editing, validate the policy and summarize which package authorities were added or corrected.

Critical findings:
- Representative run: https://github.com/githubnext/gh-aw-cao/actions/runs/33942929662
- Affected workflows: `.github/workflows/aw-failures-investigator.lock.yml`, `.github/workflows/aw-maintenance-compiler-security.lock.yml`, `.github/workflows/aw-maintenance-upgrade.lock.yml`, `.github/workflows/dependabot-release-train-updater.lock.yml`
- Evidence-supported signature: `Target authority missing: add .github/workflows/cao.json to the target default branch for live mode`
- Confidence: high for the shared cause on the three AW Doctor workflows; medium-high overall because one related Dependabot run also reported a stricter schema/package-authority validation error.

Evidence

Observed recurring precompute failures in the bounded snapshot:
- https://github.com/githubnext/gh-aw-cao/actions/runs/33942929662
- https://github.com/githubnext/gh-aw-cao/actions/runs/33942925051
- https://github.com/githubnext/gh-aw-cao/actions/runs/33942920218
- https://github.com/githubnext/gh-aw-cao/actions/runs/33942915854
- https://github.com/githubnext/gh-aw-cao/actions/runs/33942911725
- https://github.com/githubnext/gh-aw-cao/actions/runs/33942906938
- https://github.com/githubnext/gh-aw-cao/actions/runs/33942901982
- https://github.com/githubnext/gh-aw-cao/actions/runs/33942896649
- https://github.com/githubnext/gh-aw-cao/actions/runs/33942890903
- https://github.com/githubnext/gh-aw-cao/actions/runs/33942885110
- https://github.com/githubnext/gh-aw-cao/actions/runs/33942880872
- https://github.com/githubnext/gh-aw-cao/actions/runs/33942876015
- https://github.com/githubnext/gh-aw-cao/actions/runs/33942871780
- https://github.com/githubnext/gh-aw-cao/actions/runs/33942867642
- https://github.com/githubnext/gh-aw-cao/actions/runs/33942863058
- https://github.com/githubnext/gh-aw-cao/actions/runs/33941973803
- https://github.com/githubnext/gh-aw-cao/actions/runs/33941963565
- https://github.com/githubnext/gh-aw-cao/actions/runs/33941959790
- https://github.com/githubnext/gh-aw-cao/actions/runs/33941955749

Related but not merged into the main signature count because the message is more specific:
- https://github.com/githubnext/gh-aw-cao/actions/runs/33941968432 reported `Target authority file must declare version 1 and target-authority.packages.dependabot.authority`.

### Control Plane
- Correlation ID: 33944301275-198
- Central repository: githubnext/gh-aw-cao
- Control-plane run: https://github.com/githubnext/gh-aw-cao/actions/runs/33944301275

> Generated by [SelfCare / Open Source Failures](https://github.com/githubnext/gh-aw-cao/actions/runs/33944481045) · pi · gpt54 · 22.9 AIC · ⌖ 8.54 AIC · ⊞ 8.3K · [◷](https://github.com/search?q=repo%3Agithubnext%2Fgh-aw-cao+is%3Aissue+%22gh-aw-workflow-call-id%3A+githubnext%2Fgh-aw-cao%2Fself-care-open-source-failures%22&type=issues)
> - [x] expires on Sep 19, 2026, 4:30 AM UTC

Start with .github/workflows/cao.json on the protected default branch and inspect its schema/version and target-authority package entries, then compare the four affected .lock.yml workflows. Validate the policy and rerun one workflow from each affected family; done means all four pass precompute without the target-authority error.

Written by the indexing model from the issue text.