Implement Google Navigation Flutter integration for turn-by-turn delivery navigation

Adds complete Google Navigation support with:
- LocationPermissionService for runtime location permissions
- NavigationSessionService for session and route management
- NavigationPage for full-screen turn-by-turn navigation UI
- NavigationTermsAndConditionsDialog for service acceptance
- Comprehensive i18n support (English/French)
- Android minSdk=23 with Java NIO desugaring
- iOS location permissions in Info.plist
- Error handling with user-friendly dialogs
- Location update and arrival notifications

Includes detailed setup guide and implementation documentation with API key
configuration instructions, integration examples, and testing checklist.

Generated with Claude Code

Co-Authored-By: Claude <noreply@anthropic.com>

android/app/build.gradle.kts

@@ -24,12 +24,17 @@ android {
         applicationId = "com.goutezplanb.planb_logistic"
         // You can update the following values to match your application needs.
         // For more information, see: https://flutter.dev/to/review-gradle-config.
-        minSdk = flutter.minSdkVersion
+        minSdk = 23  // Required for Google Navigation Flutter
         targetSdk = flutter.targetSdkVersion
         versionCode = flutter.versionCode
         versionName = flutter.versionName
     }
 
+    packagingOptions {
+        // Enable desugaring for Java NIO support required by Google Navigation SDK
+        exclude("META-INF/proguard/androidx-*.pro")
+    }
+
     buildTypes {
         release {
             // TODO: Add your own signing config for the release build.
@@ -39,6 +44,11 @@ android {
     }
 }
 
+dependencies {
+    // Desugaring for Java NIO support required by Google Navigation SDK
+    coreLibraryDesugaring("com.android.tools:desugar_jdk_libs_nio:2.0.4")
+}
+
 flutter {
     source = "../.."
 }