fix: /config gives the state of caddy.service with the installed Caddy, for the Router Manager's Web page.

debian-package/src/usr/lib/vpn-router/web

@@ -403,7 +403,7 @@ def postgresql_databases():
 
 def details(state):
     """What /config shows: the configuration without its secrets, and what the router resolved and runs; caddy is the
-    installed Caddy, {version, source}, null when it is not installed."""
+    installed Caddy, {version, source, service}, service the state of caddy.service, null when it is not installed."""
     configuration = state.get('configuration', {})
     caddy = package_version('caddy')
     return {
@@ -420,8 +420,8 @@ def details(state):
         },
         'postgresql': postgresql_configuration(),
         # Caddy is upstream's once its repository is configured (vpn-router-caddy).
-        'caddy': {'version': caddy, 'source': 'upstream' if vpnrouter.CADDY_APT_SOURCE.is_file() else 'ubuntu'}
-                 if caddy else None,
+        'caddy': {'version': caddy, 'source': 'upstream' if vpnrouter.CADDY_APT_SOURCE.is_file() else 'ubuntu',
+                  'service': unit_state('caddy.service')} if caddy else None,
     }