llm, let compose know that the open-webui network for open-terminal is created elsewhere and not to tear it down.

tasks/workstation/linux/software/ai/llm.yml

@@ -702,6 +702,7 @@
               networks:
                 {{ llm_docker_network }}:
                   name: {{ llm_docker_network }}
+                  external: true
 
               services:
                 open-terminal: