store: opening S3 files and reading files in parallel

[djshow832]

What problem does this PR solve?

Issue Number: close #940

Problem Summary:
Opening an S3 file takes up to 200ms and makes decoding very slow.

What is changed and how it works:
Split the opening process to another goroutine to speed up reading.

Check List

Tests

• Unit test
• Integration test
• Manual test (add detailed scripts or steps below)
• No code

Testing traffic replay with dry-run and now it can catch up with the upstream cluster.

Notable changes

• Has configuration change
• Has HTTP API interfaces change
• Has tiproxyctl change
• Other user behavior changes

Release note

Please refer to Release Notes Language Style Guide to write a quality release note.

None

[ti-chi-bot]

Skipping CI for Draft Pull Request.
If you want CI signal for your change, please convert it to an actual PR.
You can still manually trigger a test run with /test all

[codecov-commenter]

Codecov Report

❌ Patch coverage is 78.72340% with 20 lines in your changes missing coverage. Please review.
⚠️ Please upload report for BASE (main@8492403). Learn more about missing BASE report.

Files with missing lines	Patch %	Lines
pkg/sqlreplay/store/rotate.go	78.72%	14 Missing and 6 partials ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #941   +/-   ##
=======================================
  Coverage        ?   67.53%           
=======================================
  Files           ?      136           
  Lines           ?    13405           
  Branches        ?        0           
=======================================
  Hits            ?     9053           
  Misses          ?     3727           
  Partials        ?      625           

Flag	Coverage Δ
unit	67.53% <78.72%> (?)

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[bb7133]

LGTM

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: bb7133

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• OWNERS [bb7133]

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[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2025-10-12 23:26:46.791281805 +0000 UTC m=+50312.868534375: ☑️ agreed by bb7133.