feat(lz-dvn): add LayerZero DVN integration

evm/contracts/apps/lz-dvn/ILayerZeroDVN.sol

@@ -0,0 +1,23 @@
+pragma solidity ^0.8.27;
+
+interface ILayerZeroDVN {
+    struct AssignJobParam {
+        uint32 dstEid;
+        bytes packetHeader;
+        bytes32 payloadHash;
+        uint64 confirmations;
+        address sender;
+    }
+
+    function assignJob(
+        AssignJobParam calldata _param,
+        bytes calldata _options
+    ) external payable returns (uint256 fee);
+
+    function getFee(
+        uint32 _dstEid,
+        uint64 _confirmations,
+        address _sender,
+        bytes calldata _options
+    ) external view returns (uint256 fee);
+}

evm/contracts/apps/lz-dvn/ILayerZeroEndpointV2.sol

@@ -0,0 +1,13 @@
+pragma solidity ^0.8.27;
+
+interface ILayerZeroEndpointV2 {
+    function getSendLibrary(
+        address _sender,
+        uint32 _dstEid
+    ) external view returns (address lib);
+
+    function getReceiveLibrary(
+        address _receiver,
+        uint32 _srcEid
+    ) external view returns (address lib, bool isDefault);
+}

evm/contracts/apps/lz-dvn/IReceiveUlnE2.sol

@@ -0,0 +1,14 @@
+pragma solidity ^0.8.27;
+
+interface IReceiveUlnE2 {
+    function verify(
+        bytes calldata _packetHeader,
+        bytes32 _payloadHash,
+        uint64 _confirmations
+    ) external;
+
+    function commitVerification(
+        bytes calldata _packetHeader,
+        bytes32 _payloadHash
+    ) external;
+}

evm/contracts/apps/lz-dvn/PacketV1Codec.sol

@@ -0,0 +1,70 @@
+pragma solidity ^0.8.27;
+
+/// @notice Decoder for LayerZero V2 packet headers.
+/// Header layout (81 bytes):
+///   [0]   uint8   version (must be 1)
+///   [1]   uint64  nonce
+///   [9]   uint32  srcEid
+///   [13]  bytes32 sender
+///   [45]  uint32  dstEid
+///   [49]  bytes32 receiver
+library PacketV1Codec {
+    uint8 internal constant PACKET_VERSION = 1;
+    uint256 internal constant PACKET_HEADER_SIZE = 81;
+
+    error ErrInvalidHeaderLength();
+    error ErrInvalidHeaderVersion();
+
+    function assertValid(
+        bytes memory header
+    ) internal pure {
+        if (header.length != PACKET_HEADER_SIZE) {
+            revert ErrInvalidHeaderLength();
+        }
+        if (uint8(header[0]) != PACKET_VERSION) {
+            revert ErrInvalidHeaderVersion();
+        }
+    }
+
+    function srcEid(
+        bytes memory header
+    ) internal pure returns (uint32 out) {
+        // data starts at header + 32; srcEid is at byte offset 9 within the data.
+        assembly {
+            out := shr(224, mload(add(header, 41)))
+        }
+    }
+
+    function dstEid(
+        bytes memory header
+    ) internal pure returns (uint32 out) {
+        // data + 45
+        assembly {
+            out := shr(224, mload(add(header, 77)))
+        }
+    }
+
+    function sender(
+        bytes memory header
+    ) internal pure returns (bytes32 out) {
+        // data + 13
+        assembly {
+            out := mload(add(header, 45))
+        }
+    }
+
+    function receiverB32(
+        bytes memory header
+    ) internal pure returns (bytes32 out) {
+        // data + 49
+        assembly {
+            out := mload(add(header, 81))
+        }
+    }
+
+    function receiverAddress(
+        bytes memory header
+    ) internal pure returns (address) {
+        return address(uint160(uint256(receiverB32(header))));
+    }
+}