sql-statements: BR / PITR SQL enhancement

[BornChanger]

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• [ ] v7.0 (TiDB 7.0 versions)
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[ti-chi-bot]

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[BornChanger]

/cc @YuJuncen

[BornChanger]

/cc @qiancai

[BornChanger]

/cc @benmaoer

[ti-chi-bot[bot]]

PR needs rebase.

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[ti-chi-bot[bot]]

@BornChanger: The following test failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
pull-verify	b6dbf74b36a6e160c2490558ae8efca268df16a5	link	true	/test pull-verify

Full PR test history. Your PR dashboard.

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