PR: Implement support for programmatic polar conversions.

[KelSolaar]

Summary

This PR implements support for programmatic polar conversions and adds the following definitions:

• colour.Lab_to_LCHab *
• colour.LCHab_to_Lab *
• colour.Luv_to_LCHuv *
• colour.LCHuv_to_Luv *
• colour.hdr_CIELab_to_hdr_CIELCHab
• colour.hdr_CIELCHab_to_hdr_CIELab
• colour.Hunter_Lab_to_Hunter_LCHab
• colour.Hunter_LCHab_to_Hunter_Lab
• colour.Hunter_Rdab_to_Hunter_RdCHab
• colour.Hunter_RdCHab_to_Hunter_Rdab
• colour.ICaCb_to_IaCH
• colour.IaCH_to_ICaCb
• colour.ICtCp_to_ItCH
• colour.ItCH_to_ICtCp
• colour.IgPgTg_to_IgCH
• colour.IgCH_to_IgPgTg
• colour.IPT_to_ICH
• colour.ICH_to_IPT
• colour.Izazbz_to_IzCH
• colour.IzCH_to_Izazbz
• colour.Jzazbz_to_JzCH
• colour.JzCH_to_Jzazbz
• colour.hdr_IPT_to_hdr_ICH
• colour.hdr_ICH_to_hdr_IPT
• colour.Oklab_to_Oklch
• colour.Oklch_to_Oklab
• colour.ProLab_to_ProLCHab
• colour.ProLCHab_to_ProLab
• colour.IPT_Ragoo2021_to_ICHPT_Ragoo2021
• colour.ICHPT_Ragoo2021_to_IPT_Ragoo2021

* Now programmatically defined.

References #1183.

Preflight

Code Style and Quality

• Unit tests have been implemented and passed.
• Pyright static checking has been run and passed.
• Pre-commit hooks have been run and passed.
• New transformations have been added to the Automatic Colour Conversion Graph.
• New transformations have been exported to the relevant namespaces, e.g. colour, colour.models.

Documentation

• New features are documented along with examples if relevant.
• The documentation is Sphinx and numpydoc compliant.

[coveralls]

coverage: 99.978%. remained the same
when pulling ed2f55a on feature/polar_conversions
into 93a54f5 on develop.