ci: pin third-party actions to commit SHAs and add least-privilege permissions (REQ-1.4.10)

- Pin all uses: refs across ci.yml, codeql.yml, compatibility.yml, pages.yml,
  pr-lint.yml, stale.yml to immutable commit SHAs with trailing # vX.Y.Z comments
- codeql.yml, pr-lint.yml, and stale.yml already carried job-level
  least-privilege permissions blocks (added upstream since the plan's
  2026-07-06 audit); no permissions changes were needed

Author: Aitomates

.github/workflows/ci.yml

@@ -18,8 +18,8 @@ jobs:
       matrix:
         os: [ubuntu-latest, windows-latest]
     steps:
-      - uses: actions/checkout@v7
-      - uses: actions/setup-node@v6
+      - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7.0.0
+      - uses: actions/setup-node@48b55a011bda9f5d6aeb4c2d9c7362e8dae4041e # v6.4.0
         with:
           node-version: 22
           cache: npm

.github/workflows/codeql.yml

@@ -19,12 +19,12 @@ jobs:
         language: [ 'typescript' ]
     steps:
     - name: Checkout repository
-      uses: actions/checkout@v7
+      uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7.0.0
     - name: Initialize CodeQL
-      uses: github/codeql-action/init@v4
+      uses: github/codeql-action/init@54f647b7e1bb85c95cddabcd46b0c578ec92bc1a # v4.36.3
       with:
         languages: ${{ matrix.language }}
     - name: Autobuild
-      uses: github/codeql-action/autobuild@v4
+      uses: github/codeql-action/autobuild@54f647b7e1bb85c95cddabcd46b0c578ec92bc1a # v4.36.3
     - name: Perform CodeQL Analysis
-      uses: github/codeql-action/analyze@v4
+      uses: github/codeql-action/analyze@54f647b7e1bb85c95cddabcd46b0c578ec92bc1a # v4.36.3

.github/workflows/compatibility.yml

@@ -20,11 +20,11 @@ jobs:
     timeout-minutes: 10
     steps:
       - name: Check out proposed contracts
-        uses: actions/checkout@v7
+        uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7.0.0
         with:
           path: candidate
           fetch-depth: 0
-      - uses: actions/setup-node@v6
+      - uses: actions/setup-node@48b55a011bda9f5d6aeb4c2d9c7362e8dae4041e # v6.4.0
         with:
           node-version: 22
           cache: npm
@@ -65,7 +65,7 @@ jobs:
           exit "$code"
       - name: Upload compatibility report
         if: always()
-        uses: actions/upload-artifact@v7
+        uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7.0.1
         with:
           name: compatibility-report
           path: candidate/compatibility-report.json

.github/workflows/pages.yml

@@ -20,13 +20,13 @@ jobs:
     runs-on: ubuntu-latest
     timeout-minutes: 15
     steps:
-      - uses: actions/checkout@v7
+      - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7.0.0
         with:
           fetch-depth: 0
-      - uses: actions/setup-python@v6
+      - uses: actions/setup-python@ece7cb06caefa5fff74198d8649806c4678c61a1 # v6.3.0
         with:
           python-version: 3.x
-      - uses: actions/setup-node@v6
+      - uses: actions/setup-node@48b55a011bda9f5d6aeb4c2d9c7362e8dae4041e # v6.4.0
         with:
           node-version: 22
           cache: npm
@@ -63,8 +63,8 @@ jobs:
           rm -f registry/CNAME
           mkdir -p site/registry
           cp -R registry/. site/registry/
-      - uses: actions/configure-pages@v6
-      - uses: actions/upload-pages-artifact@v5
+      - uses: actions/configure-pages@45bfe0192ca1faeb007ade9deae92b16b8254a0d # v6.0.0
+      - uses: actions/upload-pages-artifact@fc324d3547104276b827a68afc52ff2a11cc49c9 # v5.0.0
         with:
           path: ./site
   deploy:
@@ -80,4 +80,4 @@ jobs:
     steps:
       - name: Deploy to GitHub Pages
         id: deployment
-        uses: actions/deploy-pages@v5
+        uses: actions/deploy-pages@cd2ce8fcbc39b97be8ca5fce6e763baed58fa128 # v5.0.0

.github/workflows/pr-lint.yml

@@ -14,6 +14,6 @@ jobs:
     permissions:
       pull-requests: read
     steps:
-      - uses: amannn/action-semantic-pull-request@v6
+      - uses: amannn/action-semantic-pull-request@48f256284bd46cdaab1048c3721360e808335d50 # v6.1.1
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

.github/workflows/stale.yml

@@ -11,7 +11,7 @@ jobs:
       issues: write
       pull-requests: write
     steps:
-    - uses: actions/stale@v10
+    - uses: actions/stale@eb5cf3af3ac0a1aa4c9c45633dd1ae542a27a899 # v10.3.0
       with:
         stale-issue-message: 'This issue is stale because it has been open 60 days with no activity.'
         stale-pr-message: 'This PR is stale because it has been open 60 days with no activity.'