Fix native map services and add provider selection

wwwroot/index.html

@@ -28,6 +28,7 @@
     <script src="_framework/blazor.webview.js" autostart="false"></script>
     <script src="lib/leaflet/leaflet.js"></script>
     <script src="lib/leaflet-draw/leaflet.draw.js"></script>
+    <script src="lib/googlemutant/Leaflet.GoogleMutant.js"></script>
     <script src="lib/jszip/jszip.min.js"></script>
     <script src="lib/togeojson/togeojson.umd.js"></script>
     <script src="js/lme-map.js"></script>