Keep only curent signer

src/L1/system-contract/SystemConfig.sol

@@ -0,0 +1,30 @@
+// SPDX-License-Identifier: MIT
+pragma solidity =0.8.24;
+
+import "@openzeppelin/contracts/access/OwnableUpgradable.sol";
+
+contract SystemConfig is OwnableUpgradable {
+
+    address public currentSigner;
+
+    constructor(address _owner) {
+        _transferOwnership(_owner);
+    }
+
+    /**
+     * @dev Update the current signer.
+     *      Only the owner can call this function.
+     * @param _newSigner The address of the new authorized signer.
+     */
+    function updateSigner(address _newSigner) external onlyOwner {
+        currentSigner = _newSigner;
+    }
+
+    /**
+     * @dev Return the current authorized signer.
+     * @return The authorized signer address.
+     */
+    function getSigner() external view returns (address) {
+        return currentSigner;
+    }
+}