perf: Better GC and push_view for binviews

[ruihe774]

This PR add the logic to consider reference count when deciding whether to perform GC or not in BinaryViewArrayGeneric::maybe_gc(). Shared buffers that have multiple references won't be freed after GC, so including them when calculating memory savings, in the previous logic, does not make sense. This PR can avoid unnecessary GC in this case.

[codecov]

Codecov Report

Attention: Patch coverage is 61.76471% with 78 lines in your changes missing coverage. Please review.

Project coverage is 80.64%. Comparing base (b85654e) to head (405d7d2).
Report is 10 commits behind head on main.

Files	Patch %	Lines
crates/polars-arrow/src/array/binview/mutable.rs	42.15%	59 Missing ⚠️
crates/polars-arrow/src/array/binview/mod.rs	14.28%	18 Missing ⚠️
crates/polars-arrow/src/array/growable/binview.rs	97.95%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #17627      +/-   ##
==========================================
- Coverage   80.69%   80.64%   -0.05%     
==========================================
  Files        1484     1485       +1     
  Lines      195409   195582     +173     
  Branches     2779     2782       +3     
==========================================
+ Hits       157679   157728      +49     
- Misses      37220    37342     +122     
- Partials      510      512       +2     

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[ritchie46]

I am a bit conservative here because we had multiple problems with quadratic increasing buffers. Can you check if these issue doesn't occur again? #16989 and #15615

[ruihe774]

I am a bit conservative here because we had multiple problems with quadratic increasing buffers. Can you check if these issue doesn't occur again? #16989 and #15615

These problems were caused by not deduplicating the data buffers. I make a refactor that moves buffer deduplication from GrowableBinaryViewArray to MutableBinaryViewArray so that it can be performed when appending individual views as well. IfThenElseKernel now uses the newly introduced push_view_* and extend_views_* methods that perform deduplication transparently.

[ritchie46]

Thank you @ruihe774. It looks good. I did a run of the mentioned regressions just to be sure and all is good.