fix: support reflection tokens in deal() via checked_write transforms

[ndavd]

Problem

Reflection tokens (e.g. BabyDoge) store balances as _rOwned[account] = balance * rate, which causes deal() to hang because stdstore.find() searches for a slot where storedValue == balanceOf().

Solution

• Adds a transform parameter to find/checked_write in stdStorage. Instead of checking callResult == storedValue, it checks transform(callResult) == storedValue. When no transform is passed, it defaults to the identity transform $f(x) = x$, keeping it backward compatible.
• deal() now detects reflection tokens via reflectionFromToken(uint256,bool) (which returns the rate if called with 1,false).
• If it's a reflection token, it passes a transform of give * rate so the correct slot is found and written correctly.

Solves #740