feat(pulsenode): split Infra/Services groups, add traefik icon+href

Separates system/traefik (host+proxy infra) from the per-service
widgets into their own group, and gives the traefik widget an icon
and public dashboard link now that pulsenode's traefik widget
supports both.

pulsenode/config/config.yml

@@ -5,7 +5,7 @@ theme:
   mode: dark
 
 groups:
-  - name: Services
+  - name: Infra
     widgets:
       - type: system
         interval: 5s
@@ -13,8 +13,12 @@ groups:
       - type: traefik
         name: Traefik
         apiUrl: http://traefik:8080/api
+        icon: traefik
+        href: https://${TRAEFIK_HOST_TRAEFIK}
         interval: 15s
 
+  - name: Services
+    widgets:
       - type: service
         service: coolify
         name: Coolify