SHA-pin GitHub Actions and upgrade deprecated checkout versions

- Upgrade actions/checkout from v2/v3 to SHA-pinned v4
- SHA-pin all unshelled action tags (pages, CodeQL, scorecard,
  rust-cache, upload/download-artifact, setup-node, cache)
- Standardise scorecard-action to v2.4.0
- Fix setup-node@v6 → SHA-pinned v4

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: hyperpolymath

aggregate-library/.github/workflows/guix-nix-policy.yml

@@ -6,7 +6,7 @@ jobs:
   check:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4
       - name: Enforce Guix primary / Nix fallback
         run: |
           # Check for package manager files

aggregate-library/.github/workflows/jekyll-gh-pages.yml

@@ -28,16 +28,16 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4
       - name: Setup Pages
-        uses: actions/configure-pages@v5
+        uses: actions/configure-pages@983d7736d9b0ae728b81ab479565c72886d7745b # v5
       - name: Build with Jekyll
-        uses: actions/jekyll-build-pages@v1
+        uses: actions/jekyll-build-pages@44a6e6beabd48582f863aeeb6cb2151cc1716697 # v1
         with:
           source: ./
           destination: ./_site
       - name: Upload artifact
-        uses: actions/upload-pages-artifact@v3
+        uses: actions/upload-pages-artifact@56afc609e74202658d3ffba0e8f6dda462b719fa # v3
 
   # Deployment job
   deploy:
@@ -49,4 +49,4 @@ jobs:
     steps:
       - name: Deploy to GitHub Pages
         id: deployment
-        uses: actions/deploy-pages@v4
+        uses: actions/deploy-pages@d6db90164ac5ed86f2b6aed7e0febac5b3c0c03e # v4

aggregate-library/.github/workflows/quality.yml

@@ -7,7 +7,7 @@ jobs:
   lint:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4
 
       - name: Check file permissions
         run: |
@@ -37,7 +37,7 @@ jobs:
   docs:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4
       - name: Check documentation
         run: |
           MISSING=""

aggregate-library/.github/workflows/rsr-antipattern.yml

@@ -18,7 +18,7 @@ jobs:
   antipattern-check:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4
 
       - name: Check for TypeScript
         run: |

aggregate-library/.github/workflows/scorecard.yml

@@ -15,17 +15,17 @@ jobs:
       security-events: write
       id-token: write
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4
         with:
           persist-credentials: false
 
       - name: Run Scorecard
-        uses: ossf/scorecard-action@v2.3.1
+        uses: ossf/scorecard-action@62b2cac7ed8198b15735ed49ab1e5cf35480ba46 # v2.4.0
         with:
           results_file: results.sarif
           results_format: sarif
 
       - name: Upload results
-        uses: github/codeql-action/upload-sarif@v3
+        uses: github/codeql-action/upload-sarif@6624720a57d4c312633c7b953db2f2da5bcb4c3a # v3
         with:
           sarif_file: results.sarif

aggregate-library/.github/workflows/security-policy.yml

@@ -6,7 +6,7 @@ jobs:
   check:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4
       - name: Security checks
         run: |
           FAILED=false

aggregate-library/.github/workflows/wellknown-enforcement.yml

@@ -19,7 +19,7 @@ jobs:
   validate:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4
 
       - name: RFC 9116 security.txt validation
         run: |

packages/.github/workflows/testpr.yml

@@ -5,7 +5,7 @@ jobs:
   default:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6
         with:
           fetch-depth: 0
           ref: ${{ github.event.pull_request.head.sha }}

packages/.github/workflows/testpush.yml

@@ -5,7 +5,7 @@ jobs:
   default:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6
       - uses: iffy/install-nim@v5.1.1
         with:
           version: stable

rescript-ecosystem/cadre-router/tea-router/.github/workflows/ci.yml

@@ -24,8 +24,8 @@ jobs:
   #   name: Build
   #   runs-on: ubuntu-latest
   #   steps:
-  #     - uses: actions/checkout@v6.0.1
-  #     - uses: actions/setup-node@v4
+  #     - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6
+  #     - uses: actions/setup-node@49933ea5288caeca8642195f2b846b8bbe245a93 # v4
   #       with:
   #         node-version: '20'
   #     - run: npm ci