Add erc20 transfer with different implementation

[0xleal]

Note

Introduce MultiSendErc20 contract for batch ERC20 transfers with tests and minor tooling updates.

• Contracts:
  • Add contracts/utils/MultiSendErc20.sol providing ERC20 batch transfers:
    • multisendERC20 (pull total once, SafeERC20), multisendERC20From (per-recipient transferFrom), multisendERC20Unsafe (raw calls).
    • Enforce ARRAY_LIMIT = 200, custom errors (MismatchedArrays, ArrayLengthExceedsLimit), and Multisended event.
• Tests:
  • Add test/contracts/utils/MultiSendErc20.ts covering success, validation, and gas logging for all methods.
  • Export artifact in test/shared/artifacts.ts for MultiSendErc20.
• Tooling:
  • Add yarn 1.22.19 to .tool-versions.
  • Include @nomicfoundation/hardhat-chai-matchers in hardhat.config.ts imports.

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