chore(deps): bump actions/setup-node from 4 to 6

Bumps [actions/setup-node](https://github.com/actions/setup-node) from 4 to 6.
- [Release notes](https://github.com/actions/setup-node/releases)
- [Commits](actions/setup-node@v4...v6)

---
updated-dependencies:
- dependency-name: actions/setup-node
  dependency-version: '6'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

.github/workflows/brigadiers.yml

@@ -27,7 +27,7 @@ jobs:
     if: github.actor != 'github-actions[bot]'
     steps:
       - uses: actions/checkout@v4
-      - uses: actions/setup-node@v4
+      - uses: actions/setup-node@v6
         with:
           node-version: 22
       - name: Regenerate the Brigadiers wall

.github/workflows/ci.yml

@@ -27,7 +27,7 @@ jobs:
         uses: actions/checkout@v4
 
       - name: Setup Node ${{ matrix.node }}
-        uses: actions/setup-node@v4
+        uses: actions/setup-node@v6
         with:
           node-version: ${{ matrix.node }}
           cache: npm

.github/workflows/release.yml

@@ -72,7 +72,7 @@ jobs:
     steps:
       - uses: actions/checkout@v4
 
-      - uses: actions/setup-node@v4
+      - uses: actions/setup-node@v6
         with:
           node-version: "24"
           registry-url: "https://registry.npmjs.org"