Adaptive Positionsmeldung nach Bewegungszustand

- TrackState-Zustände (no_fix/static/moving_slow/moving_medium/moving_fast)
  mit je eigenem Meldeintervall mit/ohne Auftrag (lib/tools/track_state.dart)
- Festes Sampling (15s) statt fixem 120s-Timer; Sofortmeldung bei
  Zustandswechsel, sonst nach Zustandsintervall (mqtt_core.dart)
- track-JSON um state (String) und speed (m/s) erweitert
- Statisch-Erkennung über GPS-Genauigkeit, aktiver Auftrag = akzeptiert
  und <=15min vor ordertime
- chat_message.dart: Direktimport von objectbox.dart ergaenzt, behebt
  build_runner-Aufloesungsfehler (ChatMessage-Entity)
- Release-Build-Script (build_release_apk.sh)

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

pubspec.yaml

@@ -16,13 +16,11 @@ publish_to: 'none' # Remove this line if you wish to publish to pub.dev
 # https://developer.apple.com/library/archive/documentation/General/Reference/InfoPlistKeyReference/Articles/CoreFoundationKeys.html
 # In Windows, build-name is used as the major, minor, and patch parts
 # of the product and file versions while build-number is used as the build suffix.
-version: 352.0.0+352
+version: 354.0.0+354
 
 environment:
   sdk: '>=3.9.0 <4.0.0'
 
-
-
 # Dependencies specify other packages that your package needs in order to work.
 # To automatically upgrade your package dependencies to the latest versions
 # consider running `flutter pub upgrade --major-versions`. Alternatively,