pkg/domain: remove duplicate EtcdClient() method

[Copilot]

What problem does this PR solve?

Issue Number: close #64313

Problem Summary: (*Domain).EtcdClient() and (*Domain).GetEtcdClient() are duplicates serving identical purposes.

What changed and how does it work?

Removed EtcdClient() method and migrated all call sites to GetEtcdClient():

• pkg/domain/domain.go: Removed duplicate EtcdClient() method definition
• Updated 4 call sites in pkg/ddl/schema_test.go, pkg/session/sync_upgrade.go, pkg/session/bootstrap_test.go, and tests/realtikvtest/brietest/pitr_test.go

GetEtcdClient() chosen as standard (14 existing usages vs 4 for EtcdClient()).

Check List

Tests

• Unit test
• Integration test
• Manual test (add detailed scripts or steps below)
• 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

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[ti-chi-bot]

Hi @copilot. Thanks for your PR.

I'm waiting for a pingcap member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

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[tiprow]

Hi @copilot. Thanks for your PR.

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[lance6716]

/ok-to-test

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 74.9262%. Comparing base (5541db5) to head (c3dc20f).
⚠️ Report is 6 commits behind head on master.

Additional details and impacted files

@@               Coverage Diff                @@
##             master     #64328        +/-   ##
================================================
+ Coverage   72.7218%   74.9262%   +2.2044%     
================================================
  Files          1861       1884        +23     
  Lines        504726     512811      +8085     
================================================
+ Hits         367046     384230     +17184     
+ Misses       115367     104898     -10469     
- Partials      22313      23683      +1370     

Flag	Coverage Δ
integration	48.1935% <0.0000%> (?)
unit	72.5633% <100.0000%> (+0.2748%)	⬆️

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

Components	Coverage Δ
dumpling	52.8700% <ø> (ø)
parser	∅ <ø> (∅)
br	62.8769% <ø> (+16.6879%)	⬆️

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[lance6716]

/retest

[wuhuizuo]

@copilot please keep html comment elements in pull request description according to the pull request template!.

[Copilot]

@copilot please keep html comment elements in pull request description according to the pull request template!.

Updated the PR description to preserve all HTML comment elements from the template.

[lance6716]

/cc @D3Hunter

[lance6716]

/cc @yudongusa

[ti-chi-bot]

@lance6716: GitHub didn't allow me to request PR reviews from the following users: yudongusa.

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[ti-chi-bot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: D3Hunter, zimulala
Once this PR has been reviewed and has the lgtm label, please assign benmeadowcroft for approval. For more information see the Code Review Process.
Please ensure that each of them provides their approval before proceeding.

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Needs approval from an approver in each of these files:

• OWNERS [D3Hunter,zimulala]
• pkg/ddl/OWNERS [D3Hunter]
• pkg/domain/OWNERS [D3Hunter]
• pkg/session/OWNERS

Approvers can indicate their approval by writing /approve in a comment
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[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2025-11-07 02:30:51.083623867 +0000 UTC m=+410100.526653746: ☑️ agreed by zimulala.
• 2025-11-07 07:58:46.183286531 +0000 UTC m=+429775.626316409: ☑️ agreed by D3Hunter.