feat: use polars dataframe

[badele]

No description provided.

[codecov-commenter]

Codecov Report

Attention: 9 lines in your changes are missing coverage. Please review.

Comparison is base (4872f35) 91.53% compared to head (456445c) 89.92%.
Report is 1 commits behind head on main.

Files	Patch %	Lines
src/converter.ts	87.75%	6 Missing ⚠️
src/cfwf.ts	81.25%	3 Missing ⚠️

❗ Your organization needs to install the Codecov GitHub app to enable full functionality.

Additional details and impacted files

@@            Coverage Diff             @@
##             main      #23      +/-   ##
==========================================
- Coverage   91.53%   89.92%   -1.61%     
==========================================
  Files           6        6              
  Lines         508      556      +48     
  Branches       66       71       +5     
==========================================
+ Hits          465      500      +35     
- Misses         43       56      +13     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.