Real-time communication with frontend

- Frontend shows heatmap of most visit places
- Maximum accuracy can now be set
- Fix bug where battery chart filtered values wrongly

frontend/src/app/map/map.component.html

@@ -1,5 +1,6 @@
 <mgl-map [style]="'mapbox://styles/mapbox/dark-v10'" [zoom]="[15]" [center]="[this.lastLocation[0], this.lastLocation[1]]" *ngIf="showMap">
   <mgl-geojson-source id="locHistory" [data]="data"></mgl-geojson-source>
+  <mgl-geojson-source id="locHistoryFiltered" [data]="mostVisitData"></mgl-geojson-source>
   <mgl-geojson-source id="lastLoc" [data]="lastLocationData"></mgl-geojson-source>
     <mgl-layer
         id="locHistory"
@@ -10,6 +11,12 @@
           'line-width': 3
         }"
     ></mgl-layer>
+    <mgl-layer
+        id="locHistoryHeatmap"
+        type="heatmap"
+        source="locHistoryFiltered"
+        [paint]="mostVisitPaint"
+    ></mgl-layer>
     <mgl-layer
         id="lastLoc"
         type="circle"