Add support for automatically determining optimal Tabulator page_size

[philippjfr]

Initial attempt at letting Tabulator automatically determine the correct page_size for a particular height.

[codecov]

Codecov Report

Attention: Patch coverage is 79.41176% with 7 lines in your changes missing coverage. Please review.

Project coverage is 82.23%. Comparing base (c15e5db) to head (aa4c497).
Report is 41 commits behind head on main.

Files	Patch %	Lines
panel/tests/ui/widgets/test_tabulator.py	46.15%	7 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##             main    #6978       +/-   ##
===========================================
+ Coverage   40.37%   82.23%   +41.86%     
===========================================
  Files         314      326       +12     
  Lines       45937    48350     +2413     
===========================================
+ Hits        18545    39760    +21215     
+ Misses      27392     8590    -18802     

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