UniswapV3: Swap USDT->WETH->RPL

swap.sol

pragma solidity ^0.8.13;

import "forge-std/Script.sol";

interface UniV3 {
    struct ExactInputParams {
        bytes path;
        address recipient;
        uint256 amountIn;
        uint256 amountOutMinimum;
    }

    function exactInput(ExactInputParams memory params) external;
}

interface IERC20 {
    function approve(address, uint256) external;

    function balanceOf(address) external view returns (uint256);
}

contract CounterScript is Script {
    address USDT = address(0xdAC17F958D2ee523a2206206994597C13D831ec7);
    address WETH = address(0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2);
    address RPL = address(0xD33526068D116cE69F19A9ee46F0bd304F21A51f);
    address UNIV3 = address(0x68b3465833fb72A70ecDF485E0e4C7bD8665Fc45);

    uint24 usdt_weth_fee = 500;
    uint24 weth_rpl_fee = 10000;

    function setUp() public {}

    function run() public {
        vm.broadcast(msg.sender);
        IERC20(RPL).approve(UNIV3, type(uint256).max);

        bytes memory path = abi.encodePacked(
            USDT,
            usdt_weth_fee,
            WETH,
            weth_rpl_fee,
            RPL
        );
        uint256 amountIn = IERC20(USDT).balanceOf(msg.sender);

        // slippage. current price is at $14.98, I want to accept at most $15.20
        uint256 amountOutMinimum = ((amountIn * 10**12) / 152) * 10;

        UniV3.ExactInputParams memory input = UniV3.ExactInputParams({
            path: path,
            recipient: msg.sender,
            amountIn: amountIn,
            amountOutMinimum: amountOutMinimum
        });
        vm.broadcast(msg.sender);
        UniV3(UNIV3).exactInput(input);
    }
}

I mistakenly sent $USDT to my RocketPool wallet instead of first swapping it for $RPL, which is what I wanted to stake.

So now I'm left having to somehow swap it or transfer it out, from a wallet that I don't want to compromise in any way (i.e.: there's no way I'm gonna plug this into metamask).
ended up writing a forge script to handle this for me directly on the server where the encrypted private key file already lived