Refactor example app and add location tracking functionality with tests

packages/map-sdk/README.md

@@ -15,20 +15,24 @@ Basic usage:
 
 ```ts
 import React from 'react';
-import { MapView, Marker } from '@lynkedup/map-sdk';
+import { MapView, Marker, useLocationTracking, Polyline } from '@lynkedup/map-sdk';
 
 export default function App() {
+  const { isTracking, path, startTracking, stopTracking, clear } = useLocationTracking();
+
   return (
-    <MapView
-      style={{ flex: 1 }}
-      initialRegion={{ latitude: 37.78825, longitude: -122.4324, latitudeDelta: 0.0922, longitudeDelta: 0.0421 }}
-    >
+    <MapView style={{ flex: 1 }} initialRegion={{ latitude: 37.78825, longitude: -122.4324, latitudeDelta: 0.0922, longitudeDelta: 0.0421 }}>
       <Marker coordinate={{ latitude: 37.78825, longitude: -122.4324 }} />
+      {path.length > 1 && <Polyline coordinates={path} strokeWidth={4} strokeColor="#007AFF" />}
     </MapView>
   );
 }
 ```
 
+Tracking notes:
+- `useLocationTracking()` uses the platform geolocation API (`navigator.geolocation.watchPosition`). Request permissions on iOS/Android as usual before starting tracking.
+- It returns `{ isTracking, path, current, startTracking, stopTracking, clear }` so you can display the polyline and follow the user.
+
 ## Camera Controls 🔧
 
 This package exposes a small imperative `MapHandle` API via `ref` on `MapView`. Use it to animate the camera or fit bounds.