fix data race on lazy tx id

[asmyasnikov]

Pull request type

Please check the type of change your PR introduces:

• Bugfix
• Feature
• Code style update (formatting, renaming)
• Refactoring (no functional changes, no api changes)
• Build related changes
• Documentation content changes
• Other (please describe):

What is the current behavior?

Issue Number: #2151

What is the new behavior?

Other information

[github-actions]

summary

Inferred base version: v3.136.2
Suggested version: v3.136.3

[codecov-commenter]

Codecov Report

❌ Patch coverage is 16.77019% with 134 lines in your changes missing coverage. Please review.
✅ Project coverage is 71.65%. Comparing base (f70288e) to head (956f82a).
⚠️ Report is 45 commits behind head on master.

Files with missing lines	Patch %	Lines
internal/mock/server.go	0.00%	134 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #2152      +/-   ##
==========================================
- Coverage   74.89%   71.65%   -3.24%     
==========================================
  Files         428      428              
  Lines       37432    37572     +140     
==========================================
- Hits        28035    26923    -1112     
- Misses       8193     9434    +1241     
- Partials     1204     1215      +11     

Flag	Coverage Δ
experiment	?
go-1.21.x	71.59% <16.77%> (-0.39%)	⬇️
go-1.26.x	71.60% <16.77%> (-3.29%)	⬇️
integration	57.04% <100.00%> (-0.24%)	⬇️
macOS	45.77% <6.21%> (-0.20%)	⬇️
ubuntu	71.65% <16.77%> (-3.24%)	⬇️
unit	45.80% <6.21%> (-0.18%)	⬇️
windows	45.79% <6.21%> (-0.17%)	⬇️
ydb-24.4	56.47% <100.00%> (-0.29%)	⬇️
ydb-edge	56.75% <100.00%> (-0.31%)	⬇️
ydb-latest	56.69% <100.00%> (-0.26%)	⬇️
ydb-nightly	?

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[Copilot]

Pull request overview

This PR aims to eliminate a reported data race around lazy transaction ID materialization in topic-table transactional workflows (Issue #2151) by making LazyID’s underlying storage concurrency-safe.

Changes:

• Switched internal/tx.LazyID from a plain *string field to atomic.Pointer[string] with atomic load/store in ID() / SetTxID().
• Added a CHANGELOG entry describing the data race fix.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
internal/tx/id.go	Uses atomic load/store for the lazy transaction ID storage.
CHANGELOG.md	Documents the fix at the top of the changelog.

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[asmyasnikov]

тут же все равно возможна гонка между вызовами SetTxID() и ID() из разных горутин