feat: add merkle claim connector

contracts/mainnet/connectors/merkle-claim/events.sol

@@ -0,0 +1,11 @@
+//SPDX-License-Identifier: MIT
+pragma solidity ^0.8.2;
+
+contract Events {
+    event LogClaimed(
+        address merkleContract,
+        uint256 index,
+        uint256 amount,
+        uint256 setId
+    );
+}

contracts/mainnet/connectors/merkle-claim/interfaces.sol

@@ -0,0 +1,11 @@
+//SPDX-License-Identifier: MIT
+pragma solidity ^0.8.2;
+
+interface IMerkleDistributor {
+    function claim(
+        uint256 index,
+        address account,
+        uint256 amount,
+        bytes32[] calldata merkleProof
+    ) external;
+}

contracts/mainnet/connectors/merkle-claim/main.sol

@@ -0,0 +1,44 @@
+//SPDX-License-Identifier: MIT
+pragma solidity ^0.8.2;
+
+/**
+ * @title Merkle rewards claiming connector.
+*/
+
+import { Stores } from "../../common/stores.sol";
+import { Events } from "./events.sol";
+import { IMerkleDistributor } from "./interfaces.sol";
+
+abstract contract MerkleClaimConnector is Stores, Events {
+    
+    /**
+     * @dev Claim Merkle Rewards.
+     * @param merkleContract Address on merkle distributor contract.
+     * @param index The node index to verify the merkle proof.
+     * @param amount The amount of reward to claim.
+     * @param setId ID stores the amount of rewards claimed.
+    */
+    function claim(
+        address merkleContract,
+        uint256 index,
+        uint256 amount,
+        bytes32[] calldata merkleProof,
+        uint256 setId
+    ) external payable returns (string memory _eventName, bytes memory _eventParam) {
+        require(merkleProof.length > 0, "proofs-empty");
+
+        IMerkleDistributor merkleDistribute = IMerkleDistributor(merkleContract);
+
+        merkleDistribute.claim(index, address(this), amount, merkleProof);
+
+        setUint(setId, amount);
+
+        _eventName = "LogMerkleClaimed(address,uint256,uint256,uint256)";
+        _eventParam = abi.encode(merkleContract, index, amount, setId);
+    }
+
+}
+
+contract ConnectV2MerkleClaim is MerkleClaimConnector {
+    string public constant name = "Merkle-claim-v0";
+}