refactor(cuckoo-filter): move page cache ownership to chain

[nagisa-kunhah]

• Move cuckoo filter page-cache ownership from individual subfilters to the chain operation.
• Share cached pages across subfilters and commit dirty pages with metadata at the chain layer.
• Add slot-level undo for failed kick-out attempts while preserving previously staged page mutations.
• Separate the insert, kick-out, and expansion stages from persistence so future multi-item insert operations can reuse the same metadata and page cache before committing once.

Testing

• ./x.py check format
• cmake --build build --target kvrocks -j2
• cmake --build build --target unittest -j2
• ./build/unittest --gtest_filter='*Cuckoo*'
• ./build/unittest
  This PR was written using codex and GPT-5.6 sol

[Copilot]

🟡 Changes recommended

The shared cache can retain an unbounded number of clean pages while scanning long filter chains.

Once you've addressed the issues Copilot identified, you can request another Copilot review.

Pull request overview

Moves cuckoo-filter page-cache ownership to the chain layer, enabling shared staging and atomic persistence.

Changes:

• Shares cached pages across subfilters.
• Adds slot-level rollback for failed kick-outs.
• Separates insertion, expansion, and persistence stages.

File summaries

File	Description
src/types/cuckoo_filter_page.h	Defines undo metadata and cache APIs.
src/types/cuckoo_filter_page.cc	Implements slot mutation rollback.
src/types/cuckoo_filter_sub_filter.h	Makes subfilters borrow the shared cache.
src/types/cuckoo_filter_sub_filter.cc	Preserves staged mutations during rollback.
src/types/redis_cuckoo_chain.h	Refactors chain insertion interfaces.
src/types/redis_cuckoo_chain.cc	Centralizes cache ownership and persistence.
tests/cppunit/types/cuckoo_filter_test.cc	Tests rollback and shared-cache behavior.

Review details

• Files reviewed: 7/7 changed files
• Comments generated: 1
• Review effort level: Balanced

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[Copilot]

Copilot review overview

🟢 Approval recommended

The ownership refactor preserves atomic persistence and includes focused coverage for rollback and cache eviction.

Review effort: Balanced
Findings: None

Resolved since last review (1)

• The shared cache now retains every clean page loaded while this loop probes older subfilters. With…

[nagisa-kunhah]

Hi @jihuayu I have a minor question about my PRs: Since this PR is related to the cuckoo-filter framework, should we complete this PR first and then process the subsequent PRs, such as #3467 and #3567? I also want to know why #3467 didn't pass CI before. Should we re-trigger CI for #3467 ?

[jihuayu]

@nagisa-kunhah If #3467 and #3567 don't depend on the code in this PR, then it's not an issue.

I just forgot about PR #3467. It looks like the issue was caused by a GitHub service problem. I've already re-triggered it.

[Copilot]

🟢 Approval recommended

The refactor preserves atomic persistence and correctly covers shared-cache rollback and eviction behavior.

0 open findings

🧠 Review effort: Balanced

[jihuayu]

Hi @nagisa-kunhah I've resolved the merge conflicts. Could you please take a look and check if everything looks good? If there are no issues, I'll go ahead and merge the PR.

[nagisa-kunhah]

Hi @jihuayu , thanks for your review and for resolving the conflicts. In my original plan, I wanted to merge #3567 first so that we could replace the related subfilter API in this PR. But it's also fine to merge this PR first. This PR now looks totally good, so we can merge it. Thanks!

[jihuayu]

Sorry, I misunderstood. I'll take a look at #3567 after merging this PR.