perf: add v2 fragment file metadata to the FileMetadataCache

[jiachengdb]

After this cache, we can remove two S3 reads from an ANN query, which can reduce ~100ms query latency.

See #2642

[westonpace]

Need to clean up the lint / format changes but this looks good otherwise. I think we eventually want to push the cache down even further. I'd like to cache things like dictionaries, zone maps, etc.

I'd also like to eventually get it to the point where we the cache key is file + column that way we can avoid caching columns that we don't read.

However, this is a good short term win, thanks!

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 69.04762% with 13 lines in your changes missing coverage. Please review.

Project coverage is 79.38%. Comparing base (a23ba62) to head (cf61172).

Files	Patch %	Lines
rust/lance-file/src/v2/reader.rs	58.33%	10 Missing ⚠️
rust/lance/src/dataset/fragment.rs	83.33%	0 Missing and 3 partials ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #2647   +/-   ##
=======================================
  Coverage   79.38%   79.38%           
=======================================
  Files         221      221           
  Lines       64718    64758   +40     
  Branches    64718    64758   +40     
=======================================
+ Hits        51376    51408   +32     
- Misses      10377    10386    +9     
+ Partials     2965     2964    -1     

Flag	Coverage Δ
unittests	79.38% <69.04%> (+<0.01%)	⬆️

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[jiachengdb]

@westonpace fixed the lint errors. The remaining test failure is irrelevant.