Fix license badge and enhance usage section

[f-allian]

Updated license badge and improved usage instructions.

[github-actions]

🦙 MegaLinter status: ✅ SUCCESS

Descriptor	Linter	Files	Fixed	Errors	Elapsed time
✅ PYTHON	black	33		0	0.92s
✅ PYTHON	pylint	33		0	5.48s

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 96.29%. Comparing base (fec7c4b) to head (1d94ddf).
⚠️ Report is 3 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #360   +/-   ##
=======================================
  Coverage   96.29%   96.29%           
=======================================
  Files          28       28           
  Lines        1591     1591           
=======================================
  Hits         1532     1532           
  Misses         59       59           

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