Add WMS support and measurement functionality

- Implemented WMS layer handling for Slovenian aerial imagery and overlays for cadastral parcels and forest roads.
- Added distance measurement feature allowing users to measure distances on the map with long press interactions.
- Updated localization files for Croatian, Italian, and Slovenian languages to include new measurement and WMS-related strings.
- Enhanced the map layer model to support WMS-specific properties.
- Introduced a new tile provider for debugging WMS requests.
- Updated the drawing toolbar to include measurement mode and clear measurement functionality.
- Integrated SharedPreferences to persist overlay visibility states across app sessions.
- Added utility functions for handling the Slovenian coordinate reference system (EPSG:3794).

lib/l10n/app_localizations_de.dart

@@ -395,6 +395,29 @@ class AppLocalizationsDe extends AppLocalizations {
   @override
   String get drawRectangleDesc => 'Rechteckigen Bereich auf der Karte zeichnen';
 
+  @override
+  String get measureDistance => 'Entfernung messen';
+
+  @override
+  String get measureDistanceDesc => 'Zwei Punkte lang drücken zum Messen';
+
+  @override
+  String get clearMeasurement => 'Messung löschen';
+
+  @override
+  String distanceLabel(String distance) {
+    return 'Entfernung: $distance';
+  }
+
+  @override
+  String get longPressForSecondPoint => 'Langer Druck für zweiten Punkt';
+
+  @override
+  String get longPressToStartMeasurement => 'Langer Druck für ersten Punkt';
+
+  @override
+  String get longPressToStartNewMeasurement => 'Langer Druck für neue Messung';
+
   @override
   String get shareDrawings => 'Zeichnungen teilen';
 
@@ -1885,4 +1908,19 @@ class AppLocalizationsDe extends AppLocalizations {
 
   @override
   String get updateLater => 'Später';
+
+  @override
+  String get cadastralParcels => 'Katasterparzellen';
+
+  @override
+  String get forestRoads => 'Waldwege';
+
+  @override
+  String get showCadastralParcels => 'Katasterparzellen anzeigen';
+
+  @override
+  String get showForestRoads => 'Waldwege anzeigen';
+
+  @override
+  String get wmsOverlays => 'WMS Überlagerungen';
 }