refactor: rm callback verifier dispatcher

foundry/interfaces/ICallback.sol

@@ -0,0 +1,10 @@
+// SPDX-License-Identifier: UNLICENSED
+pragma solidity ^0.8.26;
+
+interface ICallback {
+    error UnauthorizedCaller(string exchange, address sender);
+
+    function handleCallback(
+        bytes calldata data
+    ) external returns (bytes memory result);
+}

foundry/interfaces/ICallbackVerifier.sol

@@ -1,14 +0,0 @@
-// SPDX-License-Identifier: UNLICENSED
-pragma solidity ^0.8.26;
-
-interface ICallbackVerifier {
-    error UnauthorizedCaller(string exchange, address sender);
-
-    /**
-     * @dev This method should revert if the sender is not a verified sender of the exchange.
-     */
-    function verifyCallback(
-        address sender,
-        bytes calldata data
-    ) external returns (uint256 amountOwed, address tokenOwed);
-}

foundry/interfaces/IExecutor.sol

@@ -24,10 +24,6 @@ interface IExecutor {
         uint256 givenAmount,
         bytes calldata data
     ) external payable returns (uint256 calculatedAmount);
-
-    function handleCallback(
-        bytes calldata callbackData
-    ) external returns (bytes memory result);
 }
 
 interface IExecutorErrors {