Isherwood farm mutable

[Procyonae]

Summary

None

Purpose of change

Partially addresses #62747
Mitigates #73493
Isherwood uses old fields

Describe the solution

Remakes the Isherwood farms as a mutable "Isherwood Farm Mutable", shuffling the placement of the isherwood buildings and including the same phases as the regular farm mutable after initial phases placing the Isherwood specific maps and a border of special terrain to reduce the chance of it being overrun with triffids/ants etc
Isherwood specific maps can't spawn extras anymore (the roads inbetween the buildings and the generic buildings/fields still can, a flag/field to disable extras for a whole special would be good)
Makes it globally unique
Adds NPC faction camp support for mutable specials (and translation extraction handling for them)

Describe alternatives you've considered

Also adding paddocks, I'd prefer to wait til the dairy farm is mutable too though so it can be fitting with that
The map still sticks out, I can't think of a particularly good way to make it not stick out in all possible scenarios
This is pretty basic, I'd like to add more entrance layouts and better looking building -> rural road connections in a future PR as well as just more tweaks to all the maps.
Keeping the same special id

Testing

Additional context

Example layout