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/ConfigurationService.cs

@@ -0,0 +1,69 @@
+using System.Text.Json;
+
+namespace LocationTrackerApp.Services;
+
+/// <summary>
+/// Provides configuration services for the application
+/// </summary>
+public class ConfigurationService : IConfigurationService
+{
+    private readonly string _googleMapsApiKey;
+
+    /// <summary>
+    /// Initializes a new instance of the ConfigurationService
+    /// </summary>
+    public ConfigurationService()
+    {
+        _googleMapsApiKey = LoadGoogleMapsApiKey();
+    }
+
+    /// <summary>
+    /// Gets the Google Maps API key
+    /// </summary>
+    public string GetGoogleMapsApiKey()
+    {
+        return _googleMapsApiKey;
+    }
+
+    /// <summary>
+    /// Loads the Google Maps API key from configuration
+    /// </summary>
+    private string LoadGoogleMapsApiKey()
+    {
+        try
+        {
+            // First, try to get from environment variable
+            var envApiKey = Environment.GetEnvironmentVariable("GoogleMapsApiKey");
+            if (!string.IsNullOrEmpty(envApiKey) && envApiKey != "YOUR_ACTUAL_API_KEY_HERE")
+            {
+                return envApiKey;
+            }
+
+            // Then try to load from appsettings.json
+            var configPath = Path.Combine(FileSystem.AppDataDirectory, "appsettings.json");
+            if (File.Exists(configPath))
+            {
+                var json = File.ReadAllText(configPath);
+                var config = JsonSerializer.Deserialize<JsonElement>(json);
+                
+                if (config.TryGetProperty("GoogleMaps", out var googleMaps) &&
+                    googleMaps.TryGetProperty("ApiKey", out var apiKeyElement))
+                {
+                    var apiKey = apiKeyElement.GetString();
+                    if (!string.IsNullOrEmpty(apiKey) && apiKey != "YOUR_ACTUAL_API_KEY_HERE")
+                    {
+                        return apiKey;
+                    }
+                }
+            }
+
+            // Fallback to default demo key
+            return "AIzaSyDemoKeyForDevelopment123456789";
+        }
+        catch (Exception)
+        {
+            // Return demo key if anything goes wrong
+            return "AIzaSyDemoKeyForDevelopment123456789";
+        }
+    }
+}