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/Models/LocationData.cs

@@ -0,0 +1,58 @@
+using System.ComponentModel.DataAnnotations;
+
+namespace LocationTrackerApp.Models;
+
+/// <summary>
+/// Represents a location data point stored in the database
+/// </summary>
+public class LocationData
+{
+    /// <summary>
+    /// Unique identifier for the location data point
+    /// </summary>
+    [Key]
+    public int Id { get; set; }
+
+    /// <summary>
+    /// Latitude coordinate of the location
+    /// </summary>
+    [Required]
+    public double Latitude { get; set; }
+
+    /// <summary>
+    /// Longitude coordinate of the location
+    /// </summary>
+    [Required]
+    public double Longitude { get; set; }
+
+    /// <summary>
+    /// Accuracy of the location reading in meters
+    /// </summary>
+    public double Accuracy { get; set; }
+
+    /// <summary>
+    /// Altitude of the location in meters above sea level
+    /// </summary>
+    public double? Altitude { get; set; }
+
+    /// <summary>
+    /// Speed of the device at the time of recording in meters per second
+    /// </summary>
+    public double? Speed { get; set; }
+
+    /// <summary>
+    /// Timestamp when the location was recorded
+    /// </summary>
+    [Required]
+    public DateTime Timestamp { get; set; }
+
+    /// <summary>
+    /// Session identifier to group related location points
+    /// </summary>
+    public string? SessionId { get; set; }
+
+    /// <summary>
+    /// Additional metadata or notes for this location point
+    /// </summary>
+    public string? Notes { get; set; }
+}