Add watchtower, fixes and prepare for new caddy handling

umami/docker-compose.yml

@@ -1,10 +1,18 @@
 version: '3'
 services:
-  umami:
-    image: ghcr.io/mikecao/umami:postgresql-latest
-    ports:
-      - "3013:3000"
+  app:
+    image: docker.umami.is/umami-software/umami:postgresql-latest
+    restart: always
+    labels:
+      com.centurylinklabs.watchtower.enable: true
     env_file:
       - .env
       - .secret.env
-    restart: always
+    networks:
+      services:
+        aliases:
+          - umami
+
+networks:
+  services:
+    external: true