Merge Home & Phone into a three-tab Home that knows your house

Home is now Overview | My Home | Phone. Overview leads with quick-action
tiles (focus, Do Not Disturb, health, snapshots, storage), keeps the
findings card — updates fold in, the reclaim-space prompt is gone on
purpose — and adds glance cards, the next calendar event, and weather.

My Home groups every light by Home Assistant area: the helper gained an
`areas` command (one REST template render, no websocket), and the rooms
degrade to a flat list on setups without areas. The favorites editor and
connection card moved intact. Phone gains a vitals strip — battery and
cell signal read from KDE Connect's plugin D-Bus objects, where absence
is data, not an error — beside ring, clipboard, send-a-file, and the
BlueBubbles handoff.

The retired home-phone id resolves to my-home forever via a new alias
map in SettingsRoutes (with a hasOwnProperty guard so prototype names
cannot leak into settingsPage). Storage no longer claims 0 B free — the
old page read a field the disks helper never emitted.

Contracts updated alongside; per the new workflow, the full suite runs
once at the end of the redesign (see the test backlog note).

Claude-Session: https://claude.ai/code/session_01Ms2FbjQy31TVf3CEvQhGM8

config/dot/quickshell/modules/settings/SettingsWindow.qml

@@ -6,7 +6,7 @@ import qs.services
 FloatingWindow {
     id: root
 
-    readonly property var homePhoneDiagnostics: settingsShell.homePhoneDiagnostics
+    readonly property var myHomeDiagnostics: settingsShell.myHomeDiagnostics
 
     title: "Settings"
     visible: ShellState.settingsOpen