Rename Android app to vibechat

tools/chatgui-android/app/src/main/java/com/utun/chat/data/TelecomCallManager.kt

@@ -64,7 +64,7 @@ object TelecomCallManager {
             /* registerPhoneAccount идемпотентен (перезапись по handle) и для self-managed
              * аккаунта требует только MANAGE_OWN_CALLS. getPhoneAccount() здесь не зовём —
              * он на Android 14+ требует READ_PHONE_NUMBERS, которого у нас нет. */
-            val account = PhoneAccount.builder(handle, "uTun Chat")
+            val account = PhoneAccount.builder(handle, "vibechat")
                 .setCapabilities(PhoneAccount.CAPABILITY_SELF_MANAGED)
                 .build()
             tm.registerPhoneAccount(account)

tools/chatgui-android/app/src/main/java/com/utun/chat/headless/HeadlessService.kt

@@ -25,7 +25,7 @@ class HeadlessService : Service() {
             PendingIntent.FLAG_IMMUTABLE or PendingIntent.FLAG_UPDATE_CURRENT)
 
         val notification = NotificationCompat.Builder(this, "utun_channel")
-            .setContentTitle("uTun Chat")
+            .setContentTitle("vibechat")
             .setContentText("Service running...")
             .setSmallIcon(android.R.drawable.ic_dialog_info)
             .setContentIntent(pendingIntent)
@@ -69,9 +69,9 @@ class HeadlessService : Service() {
     private fun createNotificationChannel() {
         if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
             val channel = NotificationChannel(
-                "utun_channel", "uTun Chat",
+                "utun_channel", "vibechat",
                 NotificationManager.IMPORTANCE_LOW
-            ).apply { description = "uTun Chat background service" }
+            ).apply { description = "vibechat background service" }
             getSystemService(NotificationManager::class.java).createNotificationChannel(channel)
         }
     }

tools/chatgui-android/app/src/main/java/com/utun/chat/ui/screens/ChannelListScreen.kt

@@ -55,7 +55,7 @@ fun ChannelListScreen(
     Scaffold(
         topBar = {
             TopAppBar(
-                title = { Text("uTun Chat") },
+                title = { Text("vibechat") },
                 actions = {
                     Box(
                         Modifier.size(10.dp)