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>

dashboards/dashboards.yaml

@@ -1,4 +1,8 @@
 voice-alarms: !include voice-alarms.yaml
 family-hub: !include family-hub.yaml
 at-a-glance: !include at-a-glance.yaml
-cubeops: !include cubeops.yaml
+# Each key is the dashboard's url_path, and HA requires it to contain a hyphen
+# (see homeassistant/components/lovelace: url_path validation). A hyphen-less
+# key fails validation for the whole `lovelace:` block, not just its own entry,
+# which takes every dashboard here down with it.
+cube-ops: !include cube-ops.yaml