feat: Add public key handling for avatar display and enhance paste functionality in seed phrase confirmation

app/src/main/java/com/rosetta/messenger/MainActivity.kt

@@ -205,11 +205,13 @@ fun MainScreen(
     val accountPhone = account?.publicKey?.take(16)?.let { 
         "+${it.take(1)} ${it.substring(1, 4)} ${it.substring(4, 7)}${it.substring(7)}" 
     } ?: "+7 775 9932587"
+    val accountPublicKey = account?.publicKey ?: "04c266b98ae5"
     
     ChatsListScreen(
         isDarkTheme = isDarkTheme,
         accountName = accountName,
         accountPhone = accountPhone,
+        accountPublicKey = accountPublicKey,
         onToggleTheme = onToggleTheme,
         onProfileClick = {
             // TODO: Navigate to profile