enhance: try compact small segments first if they may compose a full segment (#37709)

[tedxu]

See #37234

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pr: #37709

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 79.01%. Comparing base (fcbed3a) to head (ff3cd49).

Additional details and impacted files

@@             Coverage Diff             @@
##              2.5   #38203       +/-   ##
===========================================
+ Coverage   68.87%   79.01%   +10.13%     
===========================================
  Files         289     1353     +1064     
  Lines       25481   189424   +163943     
===========================================
+ Hits        17551   149668   +132117     
- Misses       7930    34293    +26363     
- Partials        0     5463     +5463     

Components	Coverage Δ
Client	72.16% <ø> (∅)
Core	68.87% <ø> (ø)
Go	80.79% <100.00%> (∅)

Files with missing lines	Coverage Δ
internal/datacoord/compaction_trigger.go	82.14% <100.00%> (ø)
internal/datacoord/knapsack.go	100.00% <100.00%> (ø)

... and 1062 files with indirect coverage changes