enhance: remove extra memory copy of bf16/bf16 brustforce search

[cqy123456]

issue: #37798
related knowhere pr: zilliztech/knowhere#980

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[codecov]

Codecov Report

Attention: Patch coverage is 66.66667% with 2 lines in your changes missing coverage. Please review.

Project coverage is 69.53%. Comparing base (aa0a87e) to head (540d15b).

Files with missing lines	Patch %	Lines
internal/core/src/query/SearchBruteForce.cpp	66.66%	2 Missing ⚠️

❗ There is a different number of reports uploaded between BASE (aa0a87e) and HEAD (540d15b). Click for more details.

HEAD has 1 upload less than BASE

Flag	BASE (aa0a87e)	HEAD (540d15b)
	2	1

Additional details and impacted files

@@             Coverage Diff             @@
##           master   #38751       +/-   ##
===========================================
- Coverage   81.13%   69.53%   -11.61%     
===========================================
  Files        1387      296     -1091     
  Lines      196268    26526   -169742     
===========================================
- Hits       159251    18445   -140806     
+ Misses      31421     8081    -23340     
+ Partials     5596        0     -5596     

Components	Coverage Δ
Client	∅ <ø> (∅)
Core	69.53% <66.66%> (-0.02%)	⬇️
Go	∅ <ø> (∅)

Files with missing lines	Coverage Δ
internal/core/src/query/SearchBruteForce.cpp	78.26% <66.66%> (-1.47%)	⬇️

... and 1091 files with indirect coverage changes

[mergify]

@cqy123456 cpp-unit-test check failed, comment rerun cpp-unit-test can trigger the job again.

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@cqy123456 go-sdk check failed, comment rerun go-sdk can trigger the job again.

[mergify]

@cqy123456 cpp-unit-test check failed, comment rerun cpp-unit-test can trigger the job again.

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@cqy123456 go-sdk check failed, comment rerun go-sdk can trigger the job again.

[cydrain]

Suggest to update unittest/test_bf.cpp to cover these changes.