Add heading-up compass and persist fiducial layers

wwwroot/index.html

@@ -27,6 +27,7 @@
 
     <script src="_framework/blazor.webview.js" autostart="false"></script>
     <script src="lib/leaflet/leaflet.js"></script>
+    <script src="lib/leaflet-rotate/leaflet-rotate.umd.min.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>