feat: add getLeafValue procedure

[partylikeits1983]

Resolves #2220
Builds on top of: #2238

This PR implements this solidity function in MASM:

function getLeafValue(
    uint8 leafType,
    uint32 originNetwork,
    address originAddress,
    uint32 destinationNetwork,
    address destinationAddress,
    uint256 amount,
    bytes32 metadataHash
) public pure returns (bytes32) {
    return
        keccak256(
            abi.encodePacked(
                leafType,
                originNetwork,
                originAddress,
                destinationNetwork,
                destinationAddress,
                amount,
                metadataHash
            )
        );
}

To quickly test that the masm implementation of get_leaf_value matches the agglayer Solidity implementation, you can expirement by running this basic solidity contract in Remix:

Link to Remix: Remix

Copy and paste this code into remix and run this testtest_keccak_hash_get_leaf_value:

cargo test test_keccak_hash_get_leaf_value --package miden-testing

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.20;

contract KeccakU256 {
    function getLeafValue(
        uint8 leafType,
        uint32 originNetwork,
        address originAddress,
        uint32 destinationNetwork,
        address destinationAddress,
        uint256 amount,
        bytes32 metadataHash
    ) public pure returns (bytes32) {
        return keccak256(
            abi.encodePacked(
                leafType,
                originNetwork,
                originAddress,
                destinationNetwork,
                destinationAddress,
                amount,
                metadataHash
            )
        );
    }

    function hashFixedLeafHardhat() external pure returns (bytes32) {
        uint8 leafType = 0;
        uint32 originNetwork = 0;
        address tokenAddress = 0x1234567890123456789012345678901234567890;
        uint32 destinationNetwork = 1;
        address destinationAddress = 0x0987654321098765432109876543210987654321;
        uint256 amount = 1;
        bytes32 metadataHash =
            0x2cdc14cacf6fec86a549f0e4d01e83027d3b10f29fa527c1535192c1ca1aac81;

        return getLeafValue(
            leafType,
            originNetwork,
            tokenAddress,
            destinationNetwork,
            destinationAddress,
            amount,
            metadataHash
        );
    }
}

[Copilot]

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[mmagician]

Also, for completeness we should be looking at V2 of the AggLayer contracts. For getLeafValue the logic doesn't change, but it does for its caller _verifyLeafBridge

[partylikeits1983]

@mmagician Lets first merge #2238, then will rebase this PR against agglayer branch. Same with #2270

[mmagician]

LGTM bar the duplicated file ✅

[bobbinth]

nit: might have been good to explain somewhere (briefly) that LFEAF_VALUE is just a sequential hash of LEAF_DATA using `Keccak hash function.