ci: Bump actions/download-artifact to v7 in restore-cache

download-artifact@v5 still runs on Node 20; v7 runs on Node 24 and aligns
with actions/upload-artifact@v7 used in workflows.

Co-Authored-By: Auto <noreply@anthropic.com>
Made-with: Cursor

Author: mydea

.github/actions/restore-cache/action.yml

@@ -17,7 +17,7 @@ runs:
         key: ${{ inputs.dependency_cache_key }}
 
     - name: Restore build artifacts
-      uses: actions/download-artifact@v5
+      uses: actions/download-artifact@v7
       with:
         name: build-output