chore(main): release hugr-py 0.15.6

[hugrbot]

🤖 I have created a release beep boop

0.15.6 (2026-03-19)

Features

• hugr-py: Allow linking packages and modules from Python (#2947) (329c243)
• make _composable_pass and _scope public modules (#2962) (1d6af9a), closes #2961

Bug Fixes

• allow both _composable_pass and composable_pass imports (#2965) (0a5664d)
• Always do extension resolution when loading packages and hugrs (#2953) (0086d2a)
• Correct pyo3 module definitions and add missing exception class export (#2964) (3df73f4)

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 83.87%. Comparing base (0a5664d) to head (1b1c68f).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #2948   +/-   ##
=======================================
  Coverage   83.87%   83.87%           
=======================================
  Files         268      268           
  Lines       52945    52945           
  Branches    46857    46857           
=======================================
  Hits        44410    44410           
  Misses       6266     6266           
  Partials     2269     2269           

Flag	Coverage Δ
python	88.84% <100.00%> (ø)

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