December 2024 patch

Apologies for the update size, it includes a lot of small changes and fixes of lots of different scenarios and units.

- Fallschirmjäger voices fix
- US off map mortar observer bug fix
- US armour crew fixes
- US sniper smoke grenade bug fix
- “Green Devils” scenario difficulty adjustments
- “Bastion” scenario performance threshold adjustments
- “Textbook” scenario save/load bug fix
- Optimisation of unit roster for future changes
- Various small scenario and bug fixes