Rename every remaining voxip name to daynivo, with a one-time migration

Services (daynivo-kiosk-*, daynivo-network-guard, daynivo-boot-import),
programs in /usr/lib/daynivo-kiosk, folders /etc, /var/lib, /var/log and
/var/cache daynivo-kiosk*, the system user daynivo, DAYNIVO_* settings,
the plymouth theme, network profiles daynivo-eth0/wlan0, the image stage
and its first user daynivoadmin.

install.sh moves a kiosk installed up to 1.2.x over once: old services
stopped and removed, folders moved (configuration, password, browser
profile, logs) with symlinks under the old names, the voxip user renamed
with the same uid, network profiles renamed unless a change awaits
confirmation, and old leftovers removed. Tested by upgrading a configured
1.2.0 installation in a container, and running the install a second time.

Old names keep working where people type or place them: voxip-config.json,
voxip-authorized_keys, voxip-network-reset, voxip-kiosk-ctl, and
VOXIP_DEFAULT_URL / VOXIP_DEVICE_NAME for image builds.

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

bin/daynivo-kiosk-healthcheck

@@ -0,0 +1,9 @@
+#!/usr/bin/python3 -I
+# Installed to /usr/lib/daynivo-kiosk/ by install.sh. -I: ignore PYTHON* env and user site-packages.
+import sys
+
+sys.path.insert(0, "/usr/lib/daynivo-kiosk/python")
+
+from daynivo_kiosk.healthcheck import main  # noqa: E402
+
+sys.exit(main())