Move search functions from LSDB -> HATS

[sedonaprice]

Moved lsdb.core.search submodule functions into a new hats.search submodule. The classes in the lsdb.core.search submodule remain in LSDB, as these are specifically implemented to work with LSDB catalogs.

Updated all relevant imports to import from hats.search and not lsdb.core.search.

This addresses part of #325, and helps to meet stcal usage needs (enabling only HATS as a dependency).

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 97.11%. Comparing base (ded5f0b) to head (36a0107).
⚠️ Report is 78 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1087      +/-   ##
==========================================
- Coverage   97.15%   97.11%   -0.04%     
==========================================
  Files          46       46              
  Lines        2741     2704      -37     
==========================================
- Hits         2663     2626      -37     
  Misses         78       78              

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[github-actions]

Before [ded5f0b]	After [86f7c21]	Ratio	Benchmark (Parameter)
failed	failed	n/a	benchmarks.time_lazy_crossmatch_many_columns_all_suffixes
failed	failed	n/a	benchmarks.time_lazy_crossmatch_many_columns_overlapping_suffixes
failed	failed	n/a	benchmarks.time_open_many_columns_all
90.0±1ms	96.0±3ms	1.07	benchmarks.time_kdtree_crossmatch
25.8±0.2ms	27.1±0.9ms	1.05	benchmarks.time_box_filter_on_partition
5.67±0.01s	5.87±0.03s	1.04	benchmarks.time_create_large_catalog
856±4ms	872±3ms	1.02	benchmarks.time_create_midsize_catalog
1.65±0.01s	1.68±0.04s	1.01	benchmarks.time_open_many_columns_default
589±10ms	586±10ms	0.99	benchmarks.time_open_many_columns_list
43.9±2ms	43.3±2ms	0.99	benchmarks.time_polygon_search

Some benchmarks failed or their performance regressed significantly.

[delucchi-cmu]

🚀