Rename the web interface to Daynivo Kiosk Manager with the Daynivo logo

The Daynivo mark sits on a small white tile in the navy bar, where its
navy parts would otherwise disappear; the favicon is Daynivo's too.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

config/avahi-voxip.service

@@ -1,7 +1,7 @@
 <?xml version="1.0" standalone='no'?>
 <!DOCTYPE service-group SYSTEM "avahi-service.dtd">
 <service-group>
-  <name replace-wildcards="yes">VoxIP Kiosk Manager op %h</name>
+  <name replace-wildcards="yes">Daynivo Kiosk Manager op %h</name>
   <service>
     <type>_http._tcp</type>
     <port>8080</port>