feat: add kafka backfill frontend

[xxchan]

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What's changed and what's your intention?

TODO:

• Tracking: Alter Source/table with connector #11800
• scaling
• check whether CREATE TABLE is correct

Checklist

• I have written necessary rustdoc comments
• I have added necessary unit tests and integration tests
• I have added test labels as necessary. See details.
• I have added fuzzing tests or opened an issue to track them. (Optional, recommended for new SQL features Sqlsmith: Sql feature generation #7934).
• My PR contains breaking changes. (If it deprecates some features, please create a tracking issue to remove them in the future).
• All checks passed in ./risedev check (or alias, ./risedev c)
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Documentation

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Release note

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[xxchan]

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.
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Current dependencies on/for this PR:

• feat(risedev): add some configs for monitoring #15354
• feat: add kafka backfill frontend #14465 👈
• feat(stream): add kafka backfill executor #14172
• refactor: refactor source executor (part 2) #15104
• refactor: refactor source executor (part 1) #15103
• main

This stack of pull requests is managed by Graphite.

[xxchan]

use a new PR for cleaner page #15602