ci(scorecard-enforcer): split score-threshold from publish job (OSSF run-step ban) (#37)

## Summary

This repo's `scorecard-enforcer.yml` has the OSSF publish-contract
violation that hyperpolymath/standards#304 fixed in the canonical
template. Every Scorecard run fails with:

```
webapp: scorecard job must only have steps with uses
```

## Root cause

OSSF's publish endpoint enforces a hard contract: the job that runs
`ossf/scorecard-action` with `publish_results: true` must contain ONLY
`uses:` steps. The pre-fix template's "Check minimum score" `run:` step
in the same job fails the publish step and the whole workflow run.

## Fix

Replace local file with the post-#304 standards template:
- `scorecard` job: uses-only (now includes `upload-artifact` for SARIF
hand-off)
- `check-score` job: `needs: scorecard`, downloads artifact, runs the
threshold gate

## Detection going forward

Hypatia rule WF014 in hyperpolymath/hypatia#393 catches this pattern.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: hyperpolymath

.github/workflows/scorecard-enforcer.yml

@@ -9,34 +9,70 @@ on:
     - cron: '0 6 * * 1'  # Weekly on Monday
   workflow_dispatch:
 
-permissions: read-all
+# Estate guardrail: cancel superseded runs so re-pushes / rebased PR
+# updates do not pile up queued runs against the shared account-wide
+# Actions concurrency pool. Applied only to read-only check workflows
+# (no publish/mutation), so cancelling a superseded run is always safe.
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
+permissions:
+  contents: read
 
 jobs:
+  # The OSSF Scorecard publish endpoint enforces a hard contract: the job that
+  # runs `ossf/scorecard-action` with `publish_results: true` must contain
+  # ONLY steps with `uses:` (no `run:` steps in the same job). If a `run:`
+  # step is present, the publish step fails with:
+  #   "webapp: scorecard job must only have steps with uses"
+  # (49 estate repos hit this; see ROADMAP audit 2026-05-30.)
+  #
+  # Fix: split the threshold check into a downstream job that depends on
+  # `scorecard` and consumes the SARIF artifact. The `scorecard` job stays
+  # uses-only; `check-score` is the gating job that emits the error.
   scorecard:
     runs-on: ubuntu-latest
     permissions:
       security-events: write
       id-token: write  # For OIDC
     steps:
-      - uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11 # v4
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
         with:
           persist-credentials: false
 
       - name: Run Scorecard
-        uses: ossf/scorecard-action@62b2cac7ed8198b15735ed49ab1e5cf35480ba46 # v2.4.0
+        uses: ossf/scorecard-action@4eaacf0543bb3f2c246792bd56e8cdeffafb205a # v2.4.3
         with:
           results_file: results.sarif
           results_format: sarif
           publish_results: true
 
       - name: Upload SARIF
-        uses: github/codeql-action/upload-sarif@662472033e021d55d94146f66f6058822b0b39fd # v3
+        uses: github/codeql-action/upload-sarif@c6f931105cb2c34c8f901cc885ba1e2e259cf745 # v4
         with:
           sarif_file: results.sarif
 
+      - name: Persist SARIF for downstream score-gate job
+        uses: actions/upload-artifact@330a01c490aca151604b8cf639adc76d48f6c5d4 # v5.0.0
+        with:
+          name: scorecard-results
+          path: results.sarif
+          retention-days: 1
+
+  check-score:
+    needs: scorecard
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+    steps:
+      - name: Download SARIF from scorecard job
+        uses: actions/download-artifact@018cc2cf5baa6db3ef3c5f8a56943fffe632ef53 # v5.0.0
+        with:
+          name: scorecard-results
+
       - name: Check minimum score
         run: |
-          # Parse score from results
           SCORE=$(jq -r '.runs[0].tool.driver.properties.score // 0' results.sarif 2>/dev/null || echo "0")
 
           echo "OpenSSF Scorecard Score: $SCORE"
@@ -53,7 +89,7 @@ jobs:
   check-critical:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11 # v4
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
 
       - name: Check SECURITY.md exists
         run: |