Use correct corpus versification for chapter calculation

[pmachapman]

Fixes #1013

This PR fixes a crash when drafting chapters that are not in the target versification by using the source versification when relevant.

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This change is 

[codecov-commenter]

Codecov Report

❌ Patch coverage is 0% with 2 lines in your changes missing coverage. Please review.
✅ Project coverage is 71.99%. Comparing base (a75539c) to head (b91c695).

Files with missing lines	Patch %	Lines
.../src/Serval.Translation/Services/ContractMapper.cs	0.00%	0 Missing and 1 partial ⚠️
...rc/Serval.WordAlignment/Services/ContractMapper.cs	0.00%	0 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1021      +/-   ##
==========================================
- Coverage   72.00%   71.99%   -0.02%     
==========================================
  Files         386      386              
  Lines       20886    20876      -10     
  Branches     2778     2778              
==========================================
- Hits        15040    15030      -10     
  Misses       4737     4737              
  Partials     1109     1109              

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[Enkidu93]

This makes sense. Thank you, Peter! Will SF use this chapter filtering correctly though in cases where the source and target versifications differ? E.g., if the source corpus has a book with chapters 1, 2, 3, but the target splits 3 into 3 and 4, will the scripture range provided be BOOK1-3 on the source and BOOK1-4 on the target? A bit of me thinks that we should actually have the scripture ranges just follow the first source project since the source is the anchor between training and inferencing (i.e. you need source material for both). (If I'm understanding correctly, this bug would also keep you from drafting chapters that don't exist in the target, right?) Regardless, we should specify this in the documentation. I could see it either way. One would be simpler at the monolingual corpus level, but the other would be more straightforward at the build level. What do you think?

Related to sillsdev/machine#421.

@Enkidu93 reviewed 2 files and all commit messages, and made 1 comment.
Reviewable status: complete! all files reviewed, all discussions resolved (waiting on pmachapman).