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>

tests/test_web.py

@@ -176,7 +176,7 @@ def test_pages_render(logged_in, path):
     resp = logged_in.get(path)
     assert resp.status_code == 200, path
     body = resp.get_data(as_text=True)
-    assert "VoxIP Kiosk Manager" in body and "9.9.9-test" in body
+    assert "Daynivo Kiosk Manager" in body and "9.9.9-test" in body
 
 
 def test_dashboard_masks_token(logged_in, paths):