feat: integrate flutter_local_notifications for enhanced voice call notifications

- Added flutter_local_notifications dependency to manage notifications during voice calls.
- Implemented notification handling in VoiceCallService to update call status and manage user interactions.
- Enabled wake lock functionality to keep the screen on during calls and prevent audio interruptions.
- Updated AndroidManifest.xml to include necessary permissions for Bluetooth and foreground services.
- Enhanced notification actions to allow users to mute, unmute, or end calls directly from notifications.

android/app/build.gradle.kts

@@ -31,6 +31,8 @@ android {
         // Align with modern Android Gradle Plugin requirements
         sourceCompatibility = JavaVersion.VERSION_17
         targetCompatibility = JavaVersion.VERSION_17
+        // Enable core library desugaring for flutter_local_notifications
+        isCoreLibraryDesugaringEnabled = true
     }
 
     kotlinOptions {
@@ -73,6 +75,9 @@ dependencies {
     implementation("androidx.activity:activity:1.9.2")
     implementation("androidx.core:core:1.13.1")
     implementation("androidx.activity:activity-ktx:1.9.2")
+
+    // Core library desugaring for flutter_local_notifications
+    coreLibraryDesugaring("com.android.tools:desugar_jdk_libs:2.1.4")
 }
 
 flutter {

android/app/src/main/AndroidManifest.xml

@@ -4,11 +4,15 @@
     <uses-permission android:name="android.permission.RECORD_AUDIO"/>
     <uses-permission android:name="android.permission.CAMERA"/>
     <!-- No broad media/storage permissions; use Android Photo Picker (API 33+) and SAF/share intents -->
-    
+
+    <!-- Bluetooth permissions for audio routing (Android 12+) -->
+    <uses-permission android:name="android.permission.BLUETOOTH_CONNECT" android:maxSdkVersion="32" />
+
     <!-- Background streaming permissions -->
     <uses-permission android:name="android.permission.WAKE_LOCK"/>
     <uses-permission android:name="android.permission.FOREGROUND_SERVICE"/>
     <uses-permission android:name="android.permission.FOREGROUND_SERVICE_DATA_SYNC"/>
+    <uses-permission android:name="android.permission.FOREGROUND_SERVICE_MICROPHONE"/>
     <uses-permission android:name="android.permission.POST_NOTIFICATIONS"/>
     
     <queries>
@@ -88,7 +92,7 @@
             android:name=".BackgroundStreamingService"
             android:enabled="true"
             android:exported="false"
-            android:foregroundServiceType="dataSync"/>
+            android:foregroundServiceType="dataSync|microphone"/>
         
         <!-- Don't delete the meta-data below.
              This is used by the Flutter tool to generate GeneratedPluginRegistrant.java -->

android/app/src/main/res/drawable/ic_call_end.xml

@@ -0,0 +1,9 @@
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="24dp"
+    android:height="24dp"
+    android:viewportWidth="24"
+    android:viewportHeight="24">
+    <path
+        android:fillColor="#FFFFFF"
+        android:pathData="M12,9c-1.6,0 -3.15,0.25 -4.6,0.72v3.1c0,0.39 -0.23,0.74 -0.56,0.9 -0.98,0.49 -1.87,1.12 -2.66,1.85 -0.18,0.18 -0.43,0.28 -0.7,0.28 -0.28,0 -0.53,-0.11 -0.71,-0.29L0.29,13.08c-0.18,-0.17 -0.29,-0.42 -0.29,-0.7 0,-0.28 0.11,-0.53 0.29,-0.71C3.34,8.78 7.46,7 12,7s8.66,1.78 11.71,4.67c0.18,0.18 0.29,0.43 0.29,0.71 0,0.28 -0.11,0.53 -0.29,0.71l-2.48,2.48c-0.18,0.18 -0.43,0.29 -0.71,0.29 -0.27,0 -0.52,-0.11 -0.7,-0.28 -0.79,-0.74 -1.69,-1.36 -2.67,-1.85 -0.33,-0.16 -0.56,-0.5 -0.56,-0.9v-3.1C15.15,9.25 13.6,9 12,9z"/>
+</vector>

android/app/src/main/res/drawable/ic_mic_off.xml

@@ -0,0 +1,9 @@
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="24dp"
+    android:height="24dp"
+    android:viewportWidth="24"
+    android:viewportHeight="24">
+    <path
+        android:fillColor="#FFFFFF"
+        android:pathData="M19,11h-1.7c0,0.74 -0.16,1.43 -0.43,2.05l1.23,1.23c0.56,-0.98 0.9,-2.09 0.9,-3.28zM14.98,11.17c0,-0.06 0.02,-0.11 0.02,-0.17L15,5c0,-1.66 -1.34,-3 -3,-3S9,3.34 9,5v0.18l5.98,5.99zM4.27,3L3,4.27l6.01,6.01L9.01,11c0,1.66 1.33,3 2.99,3 0.22,0 0.44,-0.03 0.65,-0.08l1.66,1.66c-0.71,0.33 -1.5,0.52 -2.31,0.52 -2.76,0 -5.3,-2.1 -5.3,-5.1L5,11c0,3.41 2.72,6.23 6,6.72L11,21h2v-3.28c0.91,-0.13 1.77,-0.45 2.54,-0.9L19.73,21 21,19.73 4.27,3z"/>
+</vector>

android/app/src/main/res/drawable/ic_mic_on.xml

@@ -0,0 +1,9 @@
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="24dp"
+    android:height="24dp"
+    android:viewportWidth="24"
+    android:viewportHeight="24">
+    <path
+        android:fillColor="#FFFFFF"
+        android:pathData="M12,14c1.66,0 2.99,-1.34 2.99,-3L15,5c0,-1.66 -1.34,-3 -3,-3S9,3.34 9,5v6c0,1.66 1.34,3 3,3zM17.3,11c0,3 -2.54,5.1 -5.3,5.1S6.7,14 6.7,11L5,11c0,3.41 2.72,6.23 6,6.72L11,21h2v-3.28c3.28,-0.48 6,-3.3 6,-6.72h-1.7z"/>
+</vector>