Upgrade GitHub Actions to Node.js 24 compatible versions

actions/checkout v4 → v7.0.0 (9c091bb)
actions/setup-node v4 → v6.4.0 (48b55a0)

Both pinned to commit SHA to suppress the "Node.js 20 is deprecated"
warning introduced when GitHub forced actions onto Node.js 24.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: tbjers

.github/workflows/action-test.yml

@@ -13,7 +13,7 @@ jobs:
   test:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7.0.0
 
       # Run the Action runner's own unit tests.
       # vitest --coverage emits coverage/coverage-summary.json (Istanbul json-summary format),

.github/workflows/deploy-dashboard.yml

@@ -21,9 +21,9 @@ jobs:
       name: ${{ github.ref == 'refs/heads/main' && 'production' || 'preview' }}
       url: ${{ steps.deploy.outputs.deployment-url }}
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7.0.0
 
-      - uses: actions/setup-node@v4
+      - uses: actions/setup-node@48b55a011bda9f5d6aeb4c2d9c7362e8dae4041e # v6.4.0
         with:
           node-version: '20'
           cache: npm