feat: implement device verification flow with new UI components and protocol handling

app/src/main/java/com/rosetta/messenger/crypto/MessageCrypto.kt

@@ -511,6 +511,23 @@ object MessageCrypto {
         encryptedKey: String,
         myPrivateKey: String
     ): String = decryptIncomingFull(ciphertext, encryptedKey, myPrivateKey).plaintext
+
+    fun decryptIncomingFullWithPlainKey(
+        ciphertext: String,
+        plainKeyAndNonce: ByteArray
+    ): DecryptedIncoming {
+        require(plainKeyAndNonce.size >= 56) { "Invalid plainKeyAndNonce size: ${plainKeyAndNonce.size}" }
+
+        val key = plainKeyAndNonce.copyOfRange(0, 32)
+        val nonce = plainKeyAndNonce.copyOfRange(32, 56)
+        val plaintext = decryptMessage(ciphertext, key.toHex(), nonce.toHex())
+        return DecryptedIncoming(plaintext, plainKeyAndNonce)
+    }
+
+    fun decryptIncomingWithPlainKey(
+        ciphertext: String,
+        plainKeyAndNonce: ByteArray
+    ): String = decryptIncomingFullWithPlainKey(ciphertext, plainKeyAndNonce).plaintext
     
     /**
      * Расшифровка MESSAGES attachment blob