Add ECDSA signature verification and enhance ComboHandler functionality

- Integrated ECDSA for signature verification in ComboHandler.
- Updated event emissions to include additional parameters for better tracking.
- Improved gas tracking during execution of combo plans.
- Enhanced database interactions for storing and retrieving plans, including conflict resolution and status updates.
- Added new dependencies for security and database management in orchestrator.

contracts/TimelockController.sol

@@ -0,0 +1,18 @@
+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.20;
+
+import "@openzeppelin/contracts/governance/TimelockController.sol";
+
+/**
+ * @title TimelockController
+ * @notice Time-lock for critical operations (upgrades, admin functions)
+ * @dev Uses OpenZeppelin's TimelockController
+ */
+contract ComboTimelock is TimelockController {
+    constructor(
+        uint256 minDelay,
+        address[] memory proposers,
+        address[] memory executors
+    ) TimelockController(minDelay, proposers, executors) {}
+}
+