docs: Mention support for Polars in the get-started section

[jrycw]

I suggest mentioning that Polars DataFrame is supported in the get-started section. This should be an attractive point for users.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 86.40%. Comparing base (7365aaa) to head (3d65e0b).
Report is 4 commits behind head on main.

Additional details and impacted files

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  Coverage   86.40%   86.40%           
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  Files          42       42           
  Lines        4700     4700           
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  Hits         4061     4061           
  Misses        639      639           

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[machow]

Hey, thanks for opening and sorry for the wait 😓 -- we're wrapping up prep for a Great Tables workshop at posit::conf(), but should get back in the swing of things within the next week!

[machow]

@jrycw thanks for writing this up -- I hope it's okay, I made some tweaks and consolidated the two pieces of example code into one. This is so helpful as a PR, it's nuts we've gone this long without mentioning polars support 😅

[rich-iannone]

Thanks!