enhance: refine variable-length-type memory usage(#38736)

[MrPresent-Han]

related: #38736

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Codecov Report

Attention: Patch coverage is 61.03896% with 60 lines in your changes missing coverage. Please review.

Project coverage is 69.22%. Comparing base (74890da) to head (c4e7f6b).
Report is 10 commits behind head on master.

❗ Current head c4e7f6b differs from pull request most recent head 6b6957f

Please upload reports for the commit 6b6957f to get more accurate results.

Files with missing lines	Patch %	Lines
internal/core/src/common/ChunkWriter.cpp	65.78%	13 Missing ⚠️
internal/core/src/common/Chunk.h	78.04%	9 Missing ⚠️
internal/core/src/mmap/ChunkedColumn.h	22.22%	7 Missing ⚠️
...rnal/core/src/segcore/ChunkedSegmentSealedImpl.cpp	22.22%	7 Missing ⚠️
internal/core/src/segcore/SegmentSealedImpl.cpp	12.50%	7 Missing ⚠️
internal/core/src/common/Chunk.cpp	70.58%	5 Missing ⚠️
internal/core/src/mmap/Column.h	20.00%	4 Missing ⚠️
internal/core/src/segcore/SegmentInterface.h	73.33%	4 Missing ⚠️
internal/core/src/segcore/SegmentGrowingImpl.cpp	0.00%	3 Missing ⚠️
internal/core/src/common/ChunkWriter.h	87.50%	1 Missing ⚠️

❌ Your patch check has failed because the patch coverage (61.03%) is below the target coverage (80.00%). You can increase the patch coverage or adjust the target coverage.
❌ Your project check has failed because the head coverage (69.22%) is below the target coverage (77.00%). You can increase the head coverage or adjust the target coverage.

❗ There is a different number of reports uploaded between BASE (74890da) and HEAD (c4e7f6b). Click for more details.

HEAD has 1 upload less than BASE

Flag	BASE (74890da)	HEAD (c4e7f6b)
	2	1

Additional details and impacted files

@@             Coverage Diff             @@
##           master   #39578       +/-   ##
===========================================
- Coverage   80.07%   69.22%   -10.86%     
===========================================
  Files        1465      302     -1163     
  Lines      203449    27120   -176329     
===========================================
- Hits       162918    18774   -144144     
+ Misses      34709     8346    -26363     
+ Partials     5822        0     -5822     

Components	Coverage Δ
Client	∅ <ø> (∅)
Core	69.22% <61.03%> (-0.17%)	⬇️
Go	∅ <ø> (∅)

Files with missing lines	Coverage Δ
internal/core/src/common/ChunkTarget.h	100.00% <ø> (ø)
internal/core/src/common/Common.h	0.00% <ø> (-100.00%)	⬇️
internal/core/src/exec/expression/Expr.h	69.28% <ø> (ø)
internal/core/src/exec/expression/TermExpr.cpp	85.04% <ø> (ø)
...ternal/core/src/segcore/ChunkedSegmentSealedImpl.h	28.57% <ø> (ø)
internal/core/src/segcore/SegmentGrowingImpl.h	69.04% <ø> (ø)
internal/core/src/segcore/SegmentSealedImpl.h	57.14% <ø> (ø)
internal/core/src/storage/PayloadReader.cpp	100.00% <100.00%> (ø)
internal/core/src/common/ChunkWriter.h	59.25% <87.50%> (+3.09%)	⬆️
internal/core/src/segcore/SegmentGrowingImpl.cpp	81.88% <0.00%> (-0.44%)	⬇️
... and 8 more

... and 1164 files with indirect coverage changes

[MrPresent-Han]

/run-cpu-e2e
rerun go-sdk
rerun ut

[MrPresent-Han]

/run-cpu-e2e

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[MrPresent-Han]

rerun ut