statistics: enhance dumpStatsDeltaToKV to return updated batch updates and ensure proper sorting

[Rustin170506]

What problem does this PR solve?

Issue Number: ref #57869, close #58903

Problem Summary:

What changed and how does it work?

1. Remove useless map update.
2. Make sure we use the right slice to update the delta map and record the historical stats meta.
   3. I also updated it to use SELECT FOR UPDATE NOWAIT to avoid the deadlock in the first place.

Check List

Tests

• Unit test
• Integration test
• Manual test
• No need to test

  • I checked and no code files have been changed.

Side effects

• Performance regression: Consumes more CPU
• Performance regression: Consumes more Memory
• Breaking backward compatibility

Documentation

• Affects user behaviors
• Contains syntax changes
• Contains variable changes
• Contains experimental features
• Changes MySQL compatibility

Release note

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

None

[codecov]

Codecov Report

Attention: Patch coverage is 69.23077% with 4 lines in your changes missing coverage. Please review.

Project coverage is 73.7997%. Comparing base (a3cc774) to head (9af1d9b).
Report is 12 commits behind head on master.

❗ Current head 9af1d9b differs from pull request most recent head 0d2e044

Please upload reports for the commit 0d2e044 to get more accurate results.

Additional details and impacted files

@@               Coverage Diff                @@
##             master     #58929        +/-   ##
================================================
+ Coverage   73.1217%   73.7997%   +0.6780%     
================================================
  Files          1680       1710        +30     
  Lines        464543     472855      +8312     
================================================
+ Hits         339682     348966      +9284     
+ Misses       103984     102323      -1661     
- Partials      20877      21566       +689     

Flag	Coverage Δ
integration	45.7430% <0.0000%> (?)
unit	72.3191% <69.2307%> (+0.0148%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Components	Coverage Δ
dumpling	52.6910% <ø> (ø)
parser	∅ <ø> (∅)
br	45.4106% <ø> (-0.0178%)	⬇️

[Rustin170506]

Tested it in our test-infra:

[Rustin170506]

🔢 Self-check (PR reviewed by myself and ready for feedback.)

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: time-and-fate, winoros

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• pkg/statistics/OWNERS [time-and-fate,winoros]

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[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2025-01-15 13:04:33.232964698 +0000 UTC m=+123744.688010831: ☑️ agreed by winoros.
• 2025-01-16 07:29:19.670832991 +0000 UTC m=+190031.125879125: ☑️ agreed by time-and-fate.

[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-8.5: #58993.