build(docker): improve security

The ports are not exposed to public by default.

build/template.env

@@ -1,9 +1,9 @@
 # == configuration for docker compose ==
 
-# port for the main application
-EXPOSE_PORT=3000
+# port for the main application. It is better to use another load balancer for the endpoint. If you want to expose the port to public, remove the `127.0.0.1:` part and only keep the port number
+EXPOSE_PORT=127.0.0.1:3000
 # port for traefik dashboard. not recommended to expose to public
-TRAEFIK_PORT=3001
+TRAEFIK_PORT=127.0.0.1:3001
 
 # docker repo name and tag. no need to modify this
 DOCKER_REPO=