Raiding causes df-ai to crash

[mrseeker]

Describe the bug
When manually trying to start a war (by going into civilisations and starting a raid) the AI will crash on the military screen.

What happened
It caused a crash when trying to assign new units to the squads that were still there.

Expected behavior
Wait for the raiders to leave, then assign a new army.

Visual reference
If applicable, paste in a screenshot or a Twitch clip.

ai version:

Dwarf Fortress 0.47.05
  Windows 64-bit
df-ai 0.47.05-r1-100-g345855e3 (Build ID: df-ai-dev-210322001)
  code 345855e39ecdb0e4614620cad12fcee01ac57f1c
DFHack 0.47.05-r1-46-gd5d41cd3 (Build ID: df-ai-dev-210322001)
  library d5d41cd374fdda6093f3be8b5b23f97e7af6c380
  structures ad1c98cf852936694300eaf8d69e91c10b7ea57f

Additional context
Anything else you'd like to add?

If you have a df-ai-debug.log file, drag or paste the file into this issue.

df-ai debug log opened. version information follows:
Dwarf Fortress 0.47.05
  Windows 64-bit
df-ai 0.47.05-r1-100-g345855e3 (Build ID: df-ai-dev-210322001)
  code 345855e39ecdb0e4614620cad12fcee01ac57f1c
DFHack 0.47.05-r1-46-gd5d41cd3 (Build ID: df-ai-dev-210322001)
  library d5d41cd374fdda6093f3be8b5b23f97e7af6c380
  structures ad1c98cf852936694300eaf8d69e91c10b7ea57f
Assertion failed on exclusive_callback.h line 88: isExpectedScreen
expected screen to be viewscreen_layer_militaryst:layer_military/Positions:, but it is viewscreen_layer_militaryst:layer_military/Positions/Squads:dwarfmode/Default