usecols investigation for various I/O functions

[eicchen]

pasting my comment from #61386 for visibility with relevant decisionmakers

As promised during the sync meeting today, I went and compiled how various read functions handle columns being specified. Functions that take usecols (read_csv, read_clipboard, read_excel, and read_hdf(undocumented)) don't take into account input order, whereas functions that ask for columns instead do (hdf, feather, parquet, orc, starata, sql).

Finally, there are also some that straight up don't take column specifiers.

I'd expect functions that use usecols to be using the same function in the backend, but I'd have to verify it if we're planning to standardize the parameter.

CSV attached below of functions tested (those with a read and write function in pandas)
does_it_use_order.csv

[mroeschke]

Thanks, but let's centralize discussion in the original issue (#61386) so closing this one