feat: create gmp tracker event interface

contracts/interfaces/IAxelarGMPTransfer.sol

@@ -0,0 +1,33 @@
+// SPDX-License-Identifier: MIT
+
+pragma solidity ^0.8.0;
+
+/**
+ * @title IAxelarGMPTransfer
+ * @dev Interface for tracking asset value transfers using General Message Passing (GMP) calls in the Axelar Network.
+ * This interface defines an event that should be emitted when a GMP transfer occurs,
+ * allowing for standardized volume tracking across different implementations.
+ */
+interface IAxelarGMPTransfer {
+    /**
+     * @dev Emitted when a GMP transfer occurs, providing details for volume tracking.
+     * @param sender The address of the caller that initiated the transfer on the source chain.
+     * @param sourceChain The Axelar chain identifier of the source chain.
+     * @param destinationChain The Axelar chain identifier of the destination chain.
+     * @param destinationAddress The address of the contract on the destination chain that receives the transfer.
+     * @param recipientAddress The address of the final recipient of the transferred assets on the destination chain.
+     * @param tokenAddress The address of the token contract on the source chain.
+     * @param amount The amount (in atomic units) of tokens transferred.
+     * @param decimals The number of decimal places for the token.
+     */
+    event AxelarGMPTransfer(
+        address indexed sender,
+        string sourceChain,
+        string destinationChain,
+        string destinationAddress,
+        string recipientAddress,
+        string tokenAddress,
+        uint256 amount,
+        uint256 decimals
+    );
+}