refactor(frontend): more work-in-progress refactors in create table handler

[BugenZhao]

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What's changed and what's your intention?

Checklist

• I have written necessary rustdoc comments.
• I have added necessary unit tests and integration tests.
• I have added test labels as necessary.
• I have added fuzzing tests or opened an issue to track them.
• My PR contains breaking changes.
• My PR changes performance-critical code, so I will run (micro) benchmarks and present the results.
• My PR contains critical fixes that are necessary to be merged into the latest release.

Documentation

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Release note

[BugenZhao]

Warning

This pull request is not mergeable via GitHub because a downstack PR is open. Once all requirements are satisfied, merge this PR as a stack on Graphite.
Learn more

• refactor(frontend): generate replace plan without relying on definition #19866
• refactor(frontend): more work-in-progress refactors in create table handler #19941 👈 (View in Graphite)
• refactor(frontend): rearrange column binding steps in create table handler #19917
• refactor(frontend): merge steps for resolving on-conflict behavior in create table handler #19916
• main

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