Add C++ rotation docs and update Python docs

[chemiskyy]

Add a new simcoon_docs header providing C++/Python docstrings for Rotation (simcoon-python-builder/include/simcoon/docs/Libraries/Maths/doc_rotation.hpp), and update the pybind wrapper to use those doc constants (rotation.cpp). Update Sphinx docs to clarify expected input shapes with a table and add a batch-rotation example for Gauss-point quantities (docs/continuum_mechanics/functions/doc_rotation.rst, docs/cpp_api/simulation/rotation.rst). This centralizes documentation strings and improves docs for batch operations and Voigt rotation helpers.

[pruliere]

Great feature !