Daynivo names for the files on the SD card and the command line tool

- daynivo-config.json, daynivo-authorized_keys and daynivo-network-reset
  on the boot partition; errors go to daynivo-config.error.txt.
- daynivo-kiosk-ctl, with voxip-kiosk-ctl as a symlink to it.
- The voxip-* names keep working, so existing SD cards and instructions
  stay valid; when both config files are present the Daynivo one is
  applied last.
- Internal names (services, /etc/voxip-kiosk, user voxip) are unchanged.

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

image/stage-voxip/00-voxip/00-run.sh

@@ -20,4 +20,4 @@ EOF_CHROOT
 
 # Instructions next to config.txt for whoever opens the boot partition.
 install -m 0644 files/voxip-kiosk/image/boot-README.txt "${ROOTFS_DIR}/boot/firmware/VOXIP-LEESMIJ.txt"
-install -m 0644 files/voxip-kiosk/image/voxip-config.example.json "${ROOTFS_DIR}/boot/firmware/voxip-config.example.json"
+install -m 0644 files/voxip-kiosk/image/daynivo-config.example.json "${ROOTFS_DIR}/boot/firmware/daynivo-config.example.json"