build: switch from yarn to npm to manage js dependencies and move js contents to root

yarn v1 is being deprecated and starts to have some issues

Signed-off-by: Thomas Citharel <tcit@tcit.fr>

src/utils/location.ts

@@ -0,0 +1,22 @@
+import ngeohash from "ngeohash";
+
+const GEOHASH_DEPTH = 9; // put enough accuracy, radius will be used anyway
+
+export const coordsToGeoHash = (
+  lat: number | undefined,
+  lon: number | undefined,
+  depth = GEOHASH_DEPTH
+): string | undefined => {
+  if (lat && lon && depth) {
+    return ngeohash.encode(lat, lon, GEOHASH_DEPTH);
+  }
+  return undefined;
+};
+
+export const geoHashToCoords = (
+  geohash: string | undefined
+): { latitude: number; longitude: number } | undefined => {
+  if (!geohash) return undefined;
+  const { latitude, longitude } = ngeohash.decode(geohash);
+  return latitude && longitude ? { latitude, longitude } : undefined;
+};