refactor: file cache receives Buf and BufMut api

[MrCroxx]

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What's changed and what's your intention?

File cache receives Buf and BufMut api to support non-continuous buffer in future.

Checklist

• I have written necessary rustdoc comments
• I have added necessary unit tests and integration tests
• 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)
• My PR changes performance-critical code. (Please run macro/micro-benchmarks and show the results.)

• My PR contains critical fixes that are necessary to be merged into the latest release. (Please check out the details)

Documentation

• My PR needs documentation updates. (Please use the Release note section below to summarize the impact on users)

Release note

If this PR includes changes that directly affect users or other significant modifications relevant to the community, kindly draft a release note to provide a concise summary of these changes. Please prioritize highlighting the impact these changes will have on users.

[codecov]

Codecov Report

Merging #12863 (203248e) into main (e1bdf78) will increase coverage by 0.06%.
The diff coverage is 27.27%.

@@            Coverage Diff             @@
##             main   #12863      +/-   ##
==========================================
+ Coverage   69.06%   69.12%   +0.06%     
==========================================
  Files        1487     1487              
  Lines      244705   244707       +2     
==========================================
+ Hits       169012   169165     +153     
+ Misses      75693    75542     -151     

Flag	Coverage Δ
rust	69.12% <27.27%> (+0.06%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files	Coverage Δ
src/storage/src/hummock/file_cache/store.rs	40.32% <27.27%> (-0.34%)	⬇️

... and 24 files with indirect coverage changes

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[hzxa21]

LGTM

[MrCroxx]

Trying another way to solve alloaction tail latency, close.