Fix lovelace url_path: cubeops -> cube-ops

HA requires a dashboard's url_path to contain a hyphen, and a key that
fails that check invalidates the entire `lovelace:` block rather than
just its own entry. `cubeops:` was added in 0c35647, so `ha core check`
has been failing since then and all four YAML dashboards -- Voice Alarms,
Family Hub, At-a-Glance and CubeOps -- were refusing to load.

Rename the key to `cube-ops`, and rename the two files alongside it so
they match, which is the convention the other three already follow
(voice-alarms -> voice-alarms.yaml).

This changes the kiosk URL to https://home.vault983.com/cube-ops. Any
wall display still pointed at /cubeops needs updating.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

themes/cubecraft.yaml

@@ -19,7 +19,7 @@
 # taking the whole themes include down.)
 #
 # Hiding the sidebar as well needs the kiosk-mode frontend plugin (HACS), which
-# is not currently installed — see dashboards/views/cubeops-dashboard.yaml.
+# is not currently installed — see dashboards/views/cube-ops-dashboard.yaml.
 
 cubecraft:
   # ─────────────────────────────────────────────────────────────────────────