planner: move more methods from StatsHandle to its sub-packages (#47749)

[ti-chi-bot]

This is an automated cherry-pick of #47749

What problem does this PR solve?

Issue Number: ref #46905

Problem Summary: planner: move more methods from StatsHandle to its sub-packages

What is changed and how it works?

planner: move more methods from StatsHandle to its sub-packages

No logical change, just refactor.

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

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: hawkingrei, hi-rustin

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[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2023-10-20 07:22:10.668974744 +0000 UTC m=+1987328.256084889: ☑️ agreed by hawkingrei.
• 2023-10-23 04:35:11.656255223 +0000 UTC m=+2236509.243365368: ☑️ agreed by hi-rustin.