Update workflow: make yq mandatory in CI (not optional)

Author: claude

.github/workflows/config-sync-check.yml

@@ -24,7 +24,7 @@ jobs:
         with:
           fetch-depth: 0
 
-      - name: Install yq (optional, script has fallback)
+      - name: Install yq
         run: |
           sudo wget -qO /usr/local/bin/yq https://github.com/mikefarah/yq/releases/latest/download/yq_linux_amd64
           sudo chmod +x /usr/local/bin/yq