Add all columns and original schema properties

[smcguire-cmu]

Adds the properties all_columns and original_schema to the dataset class. Fixes #654

[github-actions]

Before [4caa6ee]	After [de822ff]	Ratio	Benchmark (Parameter)
11.6±0.2ms	11.9±0.2ms	1.02	benchmarks.time_box_filter_on_partition
6.60±0.02s	6.60±0.02s	1	benchmarks.time_create_large_catalog
975±4ms	974±3ms	1	benchmarks.time_create_midsize_catalog
74.4±1ms	73.5±1ms	0.99	benchmarks.time_kdtree_crossmatch
24.6±0.7ms	23.4±0.4ms	0.95	benchmarks.time_polygon_search

Click here to view all benchmarks.

[codecov]

Codecov Report

Attention: Patch coverage is 85.71429% with 2 lines in your changes missing coverage. Please review.

Project coverage is 97.40%. Comparing base (4caa6ee) to head (8dde920).
Report is 246 commits behind head on main.

Files with missing lines	Patch %	Lines
src/lsdb/catalog/dataset/dataset.py	85.71%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #709      +/-   ##
==========================================
- Coverage   97.49%   97.40%   -0.09%     
==========================================
  Files          44       44              
  Lines        1915     1929      +14     
==========================================
+ Hits         1867     1879      +12     
- Misses         48       50       +2     

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