fix: update deprecated GitHub Actions to latest versions

- Update actions/download-artifact@v3 to v4
- Update actions/upload-pages-artifact@v3 to v4
- Update dawidd6/action-download-artifact@v3 to v6

Resolves CI/CD failure with deprecated artifact actions.

🤖 Generated with [Claude Code](https://claude.ai/code)

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

.github/workflows/release-pages.yml

@@ -50,7 +50,7 @@ jobs:
       - name: Download Storybook artifact (latest successful run on main)
         continue-on-error: true
         if: steps.fetch_storybook_trigger.outcome != 'success'
-        uses: dawidd6/action-download-artifact@v3
+        uses: dawidd6/action-download-artifact@v6
         with:
           github_token: ${{ secrets.GITHUB_TOKEN }}
           workflow: storybook-and-chromatic-ci.yaml
@@ -73,7 +73,7 @@ jobs:
       - name: Download Vitest reports (latest successful run on main)
         continue-on-error: true
         if: steps.fetch_vitest_trigger.outcome != 'success'
-        uses: dawidd6/action-download-artifact@v3
+        uses: dawidd6/action-download-artifact@v6
         with:
           github_token: ${{ secrets.GITHUB_TOKEN }}
           workflow: vitest-tests.yaml
@@ -89,7 +89,7 @@ jobs:
         uses: actions/configure-pages@v4
 
       - name: Upload built pages as cache
-        uses: actions/upload-pages-artifact@v3
+        uses: actions/upload-pages-artifact@v4
         with:
           name: built-pages
           path: '.pages'
@@ -124,7 +124,7 @@ jobs:
         uses: actions/checkout@v5
 
       - name: download built pages
-        uses: actions/download-artifact@v3
+        uses: actions/download-artifact@v4
         with:
           name: built-pages
           path: ./.pages