fix(ci): add Docker daemon wait and TLS env vars for DinD

Set DOCKER_HOST, DOCKER_TLS_VERIFY, DOCKER_CERT_PATH for k8s runner
DinD sidecar communication. Add 'until docker info' wait loop to
ensure daemon is ready before build starts.

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

.gitlab-ci.yml

@@ -5,6 +5,9 @@ variables:
   HARBOR_REGISTRY: harbor-in-k3s.cheverjohn.me
   HARBOR_PROJECT: iloom
   DOCKER_TLS_CERTDIR: "/certs"
+  DOCKER_HOST: tcp://localhost:2376
+  DOCKER_TLS_VERIFY: "1"
+  DOCKER_CERT_PATH: /certs/client
 
 .build-template: &build-template
   stage: build
@@ -12,6 +15,7 @@ variables:
   services:
     - docker:27-dind
   before_script:
+    - until docker info >/dev/null 2>&1; do echo "Waiting for Docker daemon..."; sleep 2; done
     - echo "$HARBOR_PASSWORD" | docker login $HARBOR_REGISTRY -u "$HARBOR_USER" --password-stdin
   script:
     - |