feat: Working VoIP calling implementation (Flutter + Android)

Working video and audio calls, as well as android integration

example/test/widget_test.dart

@@ -0,0 +1,27 @@
+// This is a basic Flutter widget test.
+//
+// To perform an interaction with a widget in your test, use the WidgetTester
+// utility in the flutter_test package. For example, you can send tap and scroll
+// gestures. You can also use WidgetTester to find child widgets in the widget
+// tree, read text, and verify that the values of widget properties are correct.
+
+import 'package:flutter/material.dart';
+import 'package:flutter_test/flutter_test.dart';
+
+import 'package:liblinphone_flutter_example/main.dart';
+
+void main() {
+  testWidgets('Verify Platform version', (WidgetTester tester) async {
+    // Build our app and trigger a frame.
+    await tester.pumpWidget(const MyApp());
+
+    // Verify that platform version is retrieved.
+    expect(
+      find.byWidgetPredicate(
+        (Widget widget) => widget is Text &&
+                           widget.data!.startsWith('Running on:'),
+      ),
+      findsOneWidget,
+    );
+  });
+}