fix a bug that would take validdocids snapshots redundantly

[klsince]

fix a bug from #12232, that would take redundant snapshots for segments w/o existing snapshot. added tests to assert the order of taking snapshots

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (9947bc5) 61.53% compared to head (5be9d03) 61.40%.
Report is 1 commits behind head on master.

Additional details and impacted files

@@             Coverage Diff              @@
##             master   #12246      +/-   ##
============================================
- Coverage     61.53%   61.40%   -0.13%     
  Complexity     1153     1153              
============================================
  Files          2416     2416              
  Lines        131196   131199       +3     
  Branches      20248    20249       +1     
============================================
- Hits          80726    80565     -161     
- Misses        44570    44729     +159     
- Partials       5900     5905       +5     

Flag	Coverage Δ
custom-integration1	<0.01% <0.00%> (ø)
integration	<0.01% <0.00%> (ø)
integration1	<0.01% <0.00%> (ø)
integration2	0.00% <0.00%> (ø)
java-11	<0.01% <0.00%> (-61.48%)	⬇️
java-21	61.40% <100.00%> (-0.01%)	⬇️
skip-bytebuffers-false	27.72% <100.00%> (-33.79%)	⬇️
skip-bytebuffers-true	61.40% <100.00%> (+0.02%)	⬆️
temurin	61.40% <100.00%> (-0.13%)	⬇️
unittests	61.40% <100.00%> (-0.13%)	⬇️
unittests1	46.41% <0.00%> (-0.22%)	⬇️
unittests2	27.73% <100.00%> (+0.03%)	⬆️

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