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 is 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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