feat(streaming): support truncating locality backfill state

[chenzl25]

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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.
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Documentation

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Release note

[chenzl25]

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

• feat(streaming): support truncating locality backfill state #23324 👈 (View in Graphite)
• feat(streaming): support locality enforcement and locality backfill #23275
• main

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