Redundant allowance check

The stakeTokens function performs an explicit allowance check before calling safeTransferFrom:

uint allowed = stakingToken.allowance(msg.sender, address(this));
require(allowed >= amount, "Allowance too low. Please approve more tokens.");
stakingToken.safeTransferFrom(msg.sender, address(this), amount);

This check is redundant since safeTransferFrom already includes an allowance verification. The duplicate check results in unnecessary gas consumption from an extra external call.