feat: Docker multi-stage build and CI/CD push

Improve Docker to multi-stage build and push to registry.

• Update central pipeline reference to main.

.gitlab-ci.yml

-include:
-  - project: 'graphpolaris/pipelines'
-    ref: fix-build-push
-    file: '.gitlab-ci.yml'
+# Comment to trigger build = 23
 
 variables:
-  DOCKERFILE_PATH: "./Dockerfile"
   CONTAINER_IMAGE: "graphpolaris/frontend"
-  IMAGE_TAG: "0.0.1-demo.0"
+  IMAGE_TAG_HELM_FILE: "/helm/staging/graphpolaris-frontend/values.yaml"
+  IMAGE_TAG_HELM_FILE_VARIABLE: "image.tag"
+
+include:
+  - project: 'graphpolaris/pipelines'
+    ref: fix-build-push
+    file: 'docker-build-push.yml'