sort imports + factorize msgNonce

Author: xenoliss

base/src/CrossChainMessenger.sol

@@ -1,13 +1,13 @@
 // SPDX-License-Identifier: MIT
 pragma solidity 0.8.28;
 
-import {MessagePasser} from "./MessagePasser.sol";
-
-import {Encoder} from "./libraries/Encoder.sol";
 import {Encoding} from "optimism/packages/contracts-bedrock/src/libraries/Encoding.sol";
 import {SafeCall} from "optimism/packages/contracts-bedrock/src/libraries/SafeCall.sol";
 import {Initializable} from "solady/utils/Initializable.sol";
 
+import {MessagePasser} from "./MessagePasser.sol";
+import {Encoder} from "./libraries/Encoder.sol";
+
 contract CrossChainMessenger is Initializable {
     //////////////////////////////////////////////////////////////
     ///                       Structs                          ///
@@ -154,12 +154,14 @@ contract CrossChainMessenger is Initializable {
     ///
     /// @param messageIxs Solana instructions to execute.
     function sendMessage(MessagePasser.Instruction[] calldata messageIxs) external {
+        uint256 messageNonce = messageNonce();
+
         MessagePasser.Instruction[] memory ixs = new MessagePasser.Instruction[](1);
         ixs[0] = MessagePasser.Instruction({
             programId: solanaMessengerProgram,
             accounts: new MessagePasser.AccountMeta[](0),
             data: Encoder.encodeMessengerPayload(
-                MessengerPayload({nonce: messageNonce(), sender: msg.sender, ixs: messageIxs})
+                MessengerPayload({nonce: messageNonce, sender: msg.sender, ixs: messageIxs})
             )
         });
 
@@ -169,7 +171,7 @@ contract CrossChainMessenger is Initializable {
         // the minimum gas limit specified by the user.
         _sendMessage(ixs);
 
-        emit SentMessage(msg.sender, messageIxs, messageNonce());
+        emit SentMessage(msg.sender, messageIxs, messageNonce);
 
         unchecked {
             ++_msgNonce;

base/src/MessagePasser.sol

@@ -1,10 +1,10 @@
 // SPDX-License-Identifier: MIT
 pragma solidity 0.8.28;
 
-// Libraries
-import {Encoder} from "./libraries/Encoder.sol";
 import {Encoding} from "optimism/packages/contracts-bedrock/src/libraries/Encoding.sol";
 
+import {Encoder} from "./libraries/Encoder.sol";
+
 /// @custom:proxied true
 /// @title L2ToL1MessagePasser
 /// @notice The L2ToL1MessagePasser is a dedicated contract where messages that are being sent from