Fix device signing/companion ID, duplicate-device crash, background updates, and add level bubble to Live Activity

- Assign the shared development team to the widget extension and watch
  complication targets, and correct the watch app's companion bundle
  identifier so on-device installs succeed after the bundle ID rename
  to de.s0.fototeddy.VanAligneiOS.
- Guard against two ConfiguredDevices sharing a peripheralID (e.g. a
  double-tapped "Sichern"), which crashed BluetoothManager's
  Dictionary(uniqueKeysWithValues:) on launch.
- Keep Bluetooth running in the background while a Live Activity is
  active, so lock screen/CarPlay keep receiving fresh readings instead
  of freezing at the last value before backgrounding.
- Render the actual bubble-level graphic (not just a static icon) in
  the Live Activity's lock screen view and expanded Dynamic Island.

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

CamperMonitor/CamperMonitorApp.swift

@@ -43,7 +43,11 @@ struct CamperMonitorApp: App {
             case .active:
                 bluetooth.start()
             case .background:
-                if !watch.wantsLiveUpdates { bluetooth.stop() }
+                // Läuft gerade eine Live Activity, muss der Neigungsmesser
+                // auch mit dunklem Bildschirm weiter Werte liefern – sonst
+                // friert die Anzeige auf Sperrbildschirm und CarPlay beim
+                // ersten Wegdrücken der App ein.
+                if !watch.wantsLiveUpdates && !levelActivity.isActive { bluetooth.stop() }
             default:
                 break
             }