Custom cross-field validator: ensures threshold does not exceed participants. Checked only after both fields pass their individual constraints, so this is the last guard.
threshold
participants
The default validation failure message.
The threshold value to validate.
Context containing the parent DTO.
true if threshold is within participants or not yet parseable.
true
Custom cross-field validator: ensures
thresholddoes not exceedparticipants. Checked only after both fields pass their individual constraints, so this is the last guard.