enhance: move segcore codes of segment into one package

[chyezh]

issue: #33285
pr: #37722

• move most cgo opeartion related to search/query into segcore package for reusing for streamingnode.
• add go unittest for segcore operations.

[sre-ci-robot]

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[mergify]

@chyezh go-sdk check failed, comment rerun go-sdk can trigger the job again.

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@chyezh E2e jenkins job failed, comment /run-cpu-e2e can trigger the job again.

[codecov]

Codecov Report

Attention: Patch coverage is 80.14981% with 106 lines in your changes missing coverage. Please review.

Project coverage is 81.00%. Comparing base (fcbed3a) to head (c7c3e22).

Files with missing lines	Patch %	Lines
internal/util/segcore/segment.go	79.23%	26 Missing and 12 partials ⚠️
internal/querynodev2/segments/segment.go	86.77%	9 Missing and 7 partials ⚠️
internal/util/segcore/requests.go	69.23%	8 Missing and 4 partials ⚠️
internal/util/segcore/reduce.go	9.09%	5 Missing and 5 partials ⚠️
internal/querynodev2/segments/collection.go	62.50%	4 Missing and 2 partials ⚠️
internal/util/segcore/collection.go	81.25%	4 Missing and 2 partials ⚠️
internal/querynodev2/segments/result.go	16.66%	4 Missing and 1 partial ⚠️
internal/querynodev2/segments/segment_l0.go	0.00%	3 Missing ⚠️
internal/util/segcore/cgo_util.go	88.46%	2 Missing and 1 partial ⚠️
internal/util/segcore/responses.go	75.00%	2 Missing and 1 partial ⚠️
... and 2 more

Additional details and impacted files

@@             Coverage Diff             @@
##              2.5   #38056       +/-   ##
===========================================
+ Coverage   68.87%   81.00%   +12.12%     
===========================================
  Files         289     1368     +1079     
  Lines       25481   190790   +165309     
===========================================
+ Hits        17551   154547   +136996     
- Misses       7930    30742    +22812     
- Partials        0     5501     +5501     

Components	Coverage Δ
Client	72.16% <ø> (∅)
Core	68.87% <ø> (ø)
Go	83.16% <80.14%> (∅)

Files with missing lines	Coverage Δ
internal/querynodev2/segments/cgo_util.go	28.57% <ø> (ø)
internal/querynodev2/segments/count_reducer.go	100.00% <100.00%> (ø)
internal/querynodev2/segments/reducer.go	90.90% <ø> (ø)
internal/querynodev2/segments/retrieve.go	82.40% <100.00%> (ø)
internal/querynodev2/segments/search.go	63.47% <100.00%> (ø)
internal/querynodev2/segments/segcore.go	100.00% <100.00%> (ø)
internal/querynodev2/segments/segment_loader.go	72.90% <100.00%> (ø)
internal/querynodev2/server.go	77.62% <100.00%> (ø)
internal/querynodev2/tasks/query_stream_task.go	79.16% <100.00%> (ø)
internal/querynodev2/tasks/query_task.go	90.17% <100.00%> (ø)
... and 14 more

... and 1055 files with indirect coverage changes

[chyezh]

/run-cpu-e2e

[chyezh]

rerun go-sdk

[mergify]

@chyezh go-sdk check failed, comment rerun go-sdk can trigger the job again.

[chyezh]

rerun go-sdk