docs: add documentation

[tlambert03]

this adds documentation at https://ino.rtfd.io

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (78390f6) 100.00% compared to head (becb86d) 100.00%.

Additional details and impacted files

@@            Coverage Diff            @@
##              main       #77   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files            5         5           
  Lines          521       521           
=========================================
  Hits           521       521           

Files	Coverage Δ
src/in_n_out/__init__.py	100.00% <ø> (ø)
src/in_n_out/_global.py	100.00% <ø> (ø)
src/in_n_out/_store.py	100.00% <ø> (ø)
src/in_n_out/_type_resolution.py	100.00% <ø> (ø)

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[codspeed-hq]

CodSpeed Performance Report

Merging #77 will not alter performance

_{Comparing tlambert03:docs (becb86d) with main (78390f6)}

Summary

✅ 5 untouched benchmarks