Add Generic Mint-Self-Burn OFT Adapter for Audit

Overview

This PR introduces a generic OFT adapter implementation designed for tokens with a specific burn pattern, created to be audit-ready without any project-specific references.

What's Added

New Contracts:

• IMintSelfBurnToken.sol - Interface for tokens with mint and self-burn functionality
• MintSelfBurnToken.sol - Generic ERC20 implementation with access-controlled mint/burn
• MintSelfBurnOFTAdapter.sol - OFT adapter for self-burn pattern tokens

Key Technical Feature: Self-Burn Pattern

This adapter is designed for tokens where the burn function has a specific signature:

function burn(uint256 amount) public onlyRole(BURNER_ROLE) {
    _burn(msg.sender, amount); // Always burns from caller, never from other addresses
}

This is different from typical burnable tokens that might allow burnFrom(address, amount) with approval.

How It Works

• Sending: Transfers tokens from user to adapter → adapter burns its own tokens (self-burn)
• Receiving: Mints new tokens directly to recipient
• Access Control: Uses OpenZeppelin's AccessControl with MINTER_ROLE and BURNER_ROLE

File Organization

Files placed in standard LayerZero package structure:

• Interface: packages/oft-evm/contracts/interfaces/IMintSelfBurnToken.sol
• Contracts: packages/oft-evm/contracts/MintSelfBurnToken.sol & MintSelfBurnOFTAdapter.sol

Usage

Any token implementing IMintSelfBurnToken can use this adapter. The adapter requires MINTER_ROLE and BURNER_ROLE permissions on the token contract.

This adapter pattern is particularly useful for projects that need cross-chain functionality with tokens that have self-burn semantics rather than delegated burning patterns.