Contract Source Code:

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.28;

contract SONAMI {
    // ERC-20 Token Metadata
    string private constant _name = "SONAMI";
    string private constant _symbol = "SONAMI";
    uint8 private constant _decimals = 18;
    
    uint256 private immutable _totalSupply;
    address private _owner;

    mapping(address => uint256) private _balances;
    mapping(address => mapping(address => uint256)) private _allowances;

    // Events
    event Transfer(address indexed from, address indexed to, uint256 amount);
    event Approval(address indexed owner, address indexed spender, uint256 amount);
    event OwnershipTransferred(address indexed oldOwner, address indexed newOwner);

    modifier onlyOwner() {
        require(msg.sender == _owner, "Caller is not the owner");
        _;
    }

    constructor(address initialOwner) {
        require(initialOwner != address(0), "Owner cannot be zero address");
        _owner = initialOwner;
        _totalSupply = 696_969_696 * 10 ** uint256(_decimals);
        _balances[initialOwner] = _totalSupply;
        emit Transfer(address(0), initialOwner, _totalSupply);
    }

    function transferOwnership(address newOwner) external onlyOwner {
        require(newOwner != address(0), "New owner cannot be zero address");
        emit OwnershipTransferred(_owner, newOwner);
        _owner = newOwner;
    }

    // ERC-20 Standard Functions
    function name() external pure returns (string memory) {
        return _name;
    }

    function symbol() external pure returns (string memory) {
        return _symbol;
    }

    function decimals() external pure returns (uint8) {
        return _decimals;
    }

    function totalSupply() external view returns (uint256) {
        return _totalSupply;
    }

    function balanceOf(address account) external view returns (uint256) {
        return _balances[account];
    }

    function transfer(address recipient, uint256 amount) external returns (bool) {
        require(recipient != address(0), "Invalid recipient address");
        require(_balances[msg.sender] >= amount, "Insufficient balance");

        _balances[msg.sender] -= amount;
        _balances[recipient] += amount;
        emit Transfer(msg.sender, recipient, amount);
        return true;
    }

    function approve(address spender, uint256 amount) external returns (bool) {
        require(spender != address(0), "Invalid spender address");

        _allowances[msg.sender][spender] = amount;
        emit Approval(msg.sender, spender, amount);
        return true;
    }

    function transferFrom(address sender, address recipient, uint256 amount) external returns (bool) {
        require(recipient != address(0), "Invalid recipient address");
        require(_balances[sender] >= amount, "Insufficient balance");
        require(_allowances[sender][msg.sender] >= amount, "Allowance exceeded");

        _balances[sender] -= amount;
        _balances[recipient] += amount;
        _allowances[sender][msg.sender] -= amount;
        emit Transfer(sender, recipient, amount);
        return true;
    }

    function allowance(address owner, address spender) external view returns (uint256) {
        return _allowances[owner][spender];
    }
}