Integration and add heat map demo

- Implemented OpenStreetMap using WebView with Leaflet.js
- Added OpenStreetMapView component with interactive map functionality
- Created heat map visualization with color-coded intensity
- Added 30 dummy location points around San Francisco Bay Area
- Implemented location tracking with real-time pin placement
- Added comprehensive UI with two-row button layout
- Features: Start/Stop tracking, Center map, Demo heat map, Clear demo, Reset map
- Added location count display and confirmation dialogs
- Updated project structure and documentation
- All functionality tested and working on Android emulator

LocationTrackerApp/Services/ILocationService.cs

@@ -0,0 +1,60 @@
+using LocationTrackerApp.Models;
+
+namespace LocationTrackerApp.Services;
+
+/// <summary>
+/// Interface for location tracking service
+/// </summary>
+public interface ILocationService
+{
+    /// <summary>
+    /// Event fired when a new location is received
+    /// </summary>
+    event EventHandler<LocationData>? LocationChanged;
+
+    /// <summary>
+    /// Event fired when location tracking status changes
+    /// </summary>
+    event EventHandler<bool>? TrackingStatusChanged;
+
+    /// <summary>
+    /// Gets the current location tracking status
+    /// </summary>
+    bool IsTracking { get; }
+
+    /// <summary>
+    /// Gets the current session ID
+    /// </summary>
+    string? CurrentSessionId { get; }
+
+    /// <summary>
+    /// Starts location tracking
+    /// </summary>
+    /// <param name="sessionId">Optional session ID for grouping location data</param>
+    /// <returns>Task representing the async operation</returns>
+    Task StartTrackingAsync(string? sessionId = null);
+
+    /// <summary>
+    /// Stops location tracking
+    /// </summary>
+    /// <returns>Task representing the async operation</returns>
+    Task StopTrackingAsync();
+
+    /// <summary>
+    /// Gets the current location
+    /// </summary>
+    /// <returns>Current location data or null if not available</returns>
+    Task<LocationData?> GetCurrentLocationAsync();
+
+    /// <summary>
+    /// Requests location permissions from the user
+    /// </summary>
+    /// <returns>True if permissions are granted, false otherwise</returns>
+    Task<bool> RequestLocationPermissionsAsync();
+
+    /// <summary>
+    /// Checks if location permissions are granted
+    /// </summary>
+    /// <returns>True if permissions are granted, false otherwise</returns>
+    Task<bool> HasLocationPermissionsAsync();
+}