* Port estrous quirks from SPLURT
This commit ports quirks related to the animal breeding cycle from the downstream server SPLURT.
* Add null check for ashwalker round_season
Adds a null value check for round_id in ashwalker estrous code to prevent possible runtime issues.
* Port DNC quirt
Ports the do-not-clone quirk from SPLURT. This change is not modular.
- Added a fix for cloning heads and brains
- Removed flavor text implications that the order was voluntary
- Quirk renamed from `DNC` to `DNC Order`
- Trait renamed from `TRAIT_NO_CLONE` to `TRAIT_DNC_ORDER`
* Modularize cloning machine DNC check
Moves the code for DNC Order quirk check in the cloning machine into modular space, and removes it from base code.
