Improve handling of breeder slave job eligibility

1. At the conclusion of the breeding exam, only approved slaves in newly-ineligible jobs are reassigned to rest.  Nurses, slaves assigned to the Spa, Master Suite fucktoys, etc, can continue in their existing assignments.
2. At the conclusion of the breeding exam, approved slaves will be automatically removed from pit fights.
3. Changes made to assignments for approved slaves at the end of the breeding exam are now listed instead of silent.
4. If a slave is ineligible to be a bodyguard because of their breeding mark, the reason listed will be "may not participate in combat" instead of "is reserved for private use".
5. Slaves with strict indentures that restrict fighting are now ineligible to be bodyguards.