expression, planner: push cast down to control function with enum type. (#24542)

[ti-srebot]

cherry-pick #24542 to release-4.0
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---

What problem does this PR solve?

Issue Number: close #23114

Problem Summary: Control function with enum type gets wrong result.

What is changed and how it works?

Proposal: xxx

What's Changed:

1. Try to push down cast funtion into control function(if/case..when/elt)
   (I have a test in mysql, ifnull(e,e) result is always string, and when compare with int, it will convert string to float)
2. Add cast to double for where condition if the eval type is ETString and the expression is control function with enum.

How it Works:

Related changes

Check List

Tests

• Unit test
• Integration test

Side effects

Release note

Fix wrong result for control function with enum type.

[ti-chi-bot]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• XuHuaiyu
• lzmhhh123

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[ti-srebot]

/run-all-tests

[ti-srebot]

@wshwsh12 you're already a collaborator in bot's repo.

[XuHuaiyu]

LGTM

[VelocityLight]

/merge

[ti-chi-bot]

This pull request has been accepted and is ready to merge.

Commit hash: 391daf9

[tiancaiamao]

/merge

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