Handle backup camera choice unavailable

[libraryaddict]

Using backupcamera ml while ML is already selected, will leave mafia in a state where it thinks it's still handling a choice.

Pushed a failing test to prove it be a thing. Fix incoming.

[codecov]

Codecov Report

Merging #1025 (e7583c5) into main (8af45d8) will increase coverage by 0.00%.
The diff coverage is 50.00%.

@@            Coverage Diff            @@
##               main    #1025   +/-   ##
=========================================
  Coverage     28.51%   28.52%           
- Complexity    13589    13595    +6     
=========================================
  Files          1031     1031           
  Lines        160598   160600    +2     
  Branches      35285    35286    +1     
=========================================
+ Hits          45801    45811   +10     
+ Misses       106360   106347   -13     
- Partials       8437     8442    +5     

Impacted Files	Coverage Δ
...e/kolmafia/textui/command/BackupCameraCommand.java	92.85% <50.00%> (-3.30%)	⬇️
...forge/kolmafia/persistence/ConcoctionDatabase.java	46.85% <0.00%> (-0.06%)	⬇️
...et/sourceforge/kolmafia/session/ChoiceManager.java	16.22% <0.00%> (+0.10%)	⬆️
...et/sourceforge/kolmafia/session/ChoiceControl.java	6.51% <0.00%> (+0.20%)	⬆️

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