Refactor documentation for faster builds

[ghisvail]

• Convert documentation to a regular Sphinx project to avoid JB's long build time.
• Provide interactive reloading to enable dynamic
• Investigate using static API docs generation
• Reorganize documentation into separate user guide, tutorial, cookbook and reference sections

Closes #11

[ghisvail]

Investigate using static API docs generation

• sphinx-autodoc2
  Recommended by the MyST documentation.
  Does not support numpydoc yet,
  see Support for NumPy-style docstrings sphinx-extensions2/sphinx-autodoc2#33

• sphinx-autoapi

[ghisvail]

A few warnings sill:

• Cyclic imports

WARNING: Cannot resolve cyclic import: medkit.audio.transcription, medkit.audio.transcription.doc_transcriber, medkit.audio.transcription.transcribed_text_document, medkit.core.text, medkit.core.text.umls_norm_attribute, medkit.core.text

• Parsing of docstrings

[AutoAPI] Mapping Data... [ 37%] /home/ghvailla/src/medkit/medkit/core/text/entity_attribute_container.p/home/ghvailla/src/medkit/.hatch/docs/lib/python3.10/site-packages/numpydoc/docscrape.py:455: UserWarning: potentially wrong underline length... 
Example: 
------- in 
Replace multiple white-spaces between alphanumeric characters and
lowercase characters with a single whitespace...
  warn(msg)
/home/ghvailla/src/medkit/.hatch/docs/lib/python3.10/site-packages/numpydoc/docscrape.py:455: UserWarning: potentially wrong underline length... 
Example: 
------- in 
Replace the character '.' between numbers
with the character ',' a space and update its span....
  warn(msg)
[AutoAPI] Mapping Data... [ 63%] /home/ghvailla/src/medkit/medkit/text/ner/hf_entity_matcher_trainable.p/home/ghvailla/src/medkit/.hatch/docs/lib/python3.10/site-packages/numpydoc/docscrape.py:455: UserWarning: Unknown section Params
  warn(msg)
...
/home/ghvailla/src/medkit/docs/api/_generated/medkit/core/text/utils/index.rst:134: WARNING: Title underline too short.

Example:
-------
/home/ghvailla/src/medkit/docs/api/_generated/medkit/core/text/utils/index.rst:329: WARNING: Title underline too short.

Example:
-------

[ghisvail]

The docs now build fast and look fine on RTD for this PR. Some more xref and MyST parsing warnings to fix, but the end is near.

[ghisvail]

Fixed API docs issues in #28

[ghisvail]

Another set of fixes to the API docs summary in #30