🔒 Refund Excess Token (If Any) To Sender in BatchDistributor

[jaglinux]

We need to return excess token in distribute_token(), similar to distribute_ether() which refunds excess ether to msg.sender

If this is ok, I will work on the PR to add the code and test case.

[pcaversaccio]

@jaglinux can you please use issues for such requests, thx.

There is no such case as excess tokens for distribute_token since this works differently as for msg.value. There is no native way to handle tokens in the EVM! First you have to approve the amount you want to transfer and thereafter the exact amount is transferred via transferFrom during the distribute_token function call. Only if all tokens are distributed, the call will succeed. You don't send tokens directly to the contract but it's a combination of approve and distribute_token.