fix: add DNS diagnostics to npm-install-dashboard CI step

.woodpecker/build-3.yml

@@ -191,8 +191,24 @@ steps:
     depends_on: []
   npm-install-dashboard:
     image: registry.celestium.life/dockerhub-cache/library/node:24-alpine
+    environment:
+      - NODE_OPTIONS=--dns-result-order=ipv4first
     commands:
-      - cd frontend && NODE_OPTIONS="--dns-result-order=ipv4first" npm ci
+      - echo "=== DNS diagnostics ==="
+      - cat /etc/resolv.conf
+      - echo "=== Testing IPv4 connectivity to registry.npmjs.org ==="
+      - wget -4 --timeout=10 --spider https://registry.npmjs.org/ 2>&1 || echo "IPv4 wget FAILED"
+      - echo "=== Testing IPv6 connectivity (expect failure) ==="
+      - wget -6 --timeout=5 --spider https://registry.npmjs.org/ 2>&1 || echo "IPv6 wget FAILED (expected)"
+      - echo "=== npm/node versions ==="
+      - node --version
+      - npm --version
+      - echo "=== Setting npm to IPv4-only ==="
+      - npm config set prefer-ip-address-family 4
+      - npm config set fetch-timeout 60000
+      - npm config set loglevel http
+      - echo "=== Starting npm ci ==="
+      - cd frontend && npm ci
     backend_options:
       kubernetes:
         resources: