CI cleanup: delete ci-rerun.yml and streamline squad-ci.yml #1000

Problem

The CI infrastructure has accumulated complexity that causes failures and spin without proportional value.

1. ci-rerun.yml — delete entirely

A manual workflow_dispatch workflow created to re-run CI on fork PRs (commit e5bf27d). It duplicates build/test steps from squad-ci.yml and drifts out of sync.

Why it's safe to delete:

• GitHub's built-in Approve and run button handles fork PRs natively
• The Squad CI / rerun status check is NOT a required check — gives a false green signal
• All build steps are duplicated from squad-ci.yml and already stale (e.g., ci-rerun installs Playwright browsers inline but squad-ci uses the setup-squad-node action)
• Only 6 commits in its history — minimal investment

2. squad-ci.yml — review and streamline (852 lines, 9 jobs)

Current jobs: changes, docs-quality, test, policy-gates, exports-map-check, samples-build, publish-policy, export-smoke-test, scope-check

Review each for:

• Failure rate vs. value — are any of these gates causing frequent failures without catching real bugs?
• Redundancy — do any jobs overlap in what they check?
• Weight — 852 lines is a lot of CI. Can gates be consolidated?
• Path filtering — the changes job does path filtering but not all downstream jobs use it. Tighten skip conditions to reduce wasted runs.

3. setup-squad-node composite action — keep but verify

The shared action is good (DRY pattern). But its comment header references ci-rerun.yml as a consumer — update after deletion.

4. Fix broken script tests (pre-existing on dev)

The dev branch has been red since PR #996 was merged. Three test files are failing:

These failures block all PRs from passing CI. Fixing them is prerequisite to merging any other work.

Action items

• Delete .github/workflows/ci-rerun.yml
• Update .github/actions/setup-squad-node/action.yml comment header (remove ci-rerun reference)
• Verify no branch protection rules reference the Squad CI / rerun status check
• Audit each job in squad-ci.yml for failure rate vs. value
• Consolidate or remove low-value gates
• Ensure all jobs respect path filtering (skip when their inputs didn't change)
• Target: get squad-ci.yml under 600 lines
• Fix or remove test/scripts/check-squad-leakage.test.ts
• Fix or remove test/scripts/security-review.test.ts
• Fix or remove test/scripts/security-review-skills.test.ts (missing scripts/security-review.mjs)
• Verify dev branch CI is green after fixes

Context

Identified during CI workflow review session. Brady's hypothesis: these CI files are the source of a lot of failures and spin we don't need. Analysis confirmed ci-rerun.yml is fully redundant, and squad-ci.yml has grown to 852 lines / 9 jobs and could benefit from a trim. Broken script tests discovered during PR #1001/#1002 CI investigation — pre-existing failures on dev since PR #996.