📝 New and improved project documentation

[burgholzer]

Description

This PR brings some quite substantial documentation improvements.
This include extensive documentation for all classes, methods and functions that are part of the Python package.
It also includes updates to the general documentation building pipeline that make it easier to write notebooks for docs purely in Markdown and provide nicer LaTeX output.

This should set the new best practice for writing documentation within the MQT.

Checklist:

• The pull request only contains commits that are related to it.
• I have added appropriate tests and documentation.
• I have made sure that all CI jobs on GitHub pass.
• The pull request introduces no new warnings and follows the project's style guidelines.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 91.4%. Comparing base (5649e0c) to head (0b69f4c).
Report is 2 commits behind head on main.

Additional details and impacted files

@@          Coverage Diff          @@
##            main    #589   +/-   ##
=====================================
  Coverage   91.4%   91.4%           
=====================================
  Files        131     131           
  Lines      14091   14091           
  Branches    2250    2250           
=====================================
  Hits       12885   12885           
  Misses      1206    1206           

Flag	Coverage Δ		*Carryforward flag
cpp	91.1% <ø> (ø)		Carriedforward from 123b9c7
python	99.5% <100.0%> (ø)

*This pull request uses carry forward flags. Click here to find out more.

Files	Coverage Δ
src/mqt/core/__init__.py	100.0% <ø> (ø)
src/mqt/core/__main__.py	100.0% <100.0%> (ø)
src/mqt/core/_commands.py	100.0% <ø> (ø)
src/mqt/core/evaluation.py	99.4% <100.0%> (ø)
src/mqt/core/io.py	100.0% <ø> (ø)
src/mqt/core/plugins/qiskit.py	99.5% <100.0%> (+<0.1%)	⬆️