ci(workflows): pin github actions to commit hashes

Updated all GitHub Actions dependencies across workflows to use full commit SHAs instead of mutable version tags (e.g., `actions/checkout`, `actions/setup-node`, and `actions/stale`). This hardens the CI/CD pipeline by ensuring action dependencies are strictly immutable and prevents potential supply chain attacks.

.github/workflows/stale.yml

@@ -11,7 +11,7 @@ jobs:
         name: Label
         runs-on: ubuntu-latest
         steps:
-            - uses: actions/stale@v10
+            - uses: actions/stale@b5d41d4e1d5dceea10e7104786b73624c18a190f # v10.2.0
               with:
                   repo-token: ${{ secrets.GITHUB_TOKEN }}
                   days-before-stale: 3