Convert docstrings to numpydoc style and refactor API docs

[taldcroft]

Description

This converts all the docstrings to numpydoc style and refactors the API docs into separate files.

The automated update was done with below followed by some hand-edits to fix things up and make minor improvements along the way.

from skare3_tools.scripts import convert_numpydoc
convert_numpydoc.convert_directory_to_numpydoc("kadi")

Interface impacts

Testing

Unit tests

• Mac

(ska3-perf) ➜  kadi git:(numpydoc) git rev-parse HEAD
c2c2b9c775b7d29919feea5bdd2411627c4554e8
(ska3-perf) ➜  kadi git:(numpydoc) pytest kadi             
==================================================== test session starts ====================================================
platform darwin -- Python 3.10.8, pytest-7.2.1, pluggy-1.0.0
rootdir: /Users/aldcroft/git, configfile: pytest.ini
plugins: timeout-2.1.0, anyio-3.6.2
collected 199 items                                                                                                         

kadi/commands/tests/test_commands.py ...........................................................................      [ 37%]
kadi/commands/tests/test_states.py ......................x.............................................x............. [ 78%]
..........                                                                                                            [ 83%]
kadi/tests/test_events.py ..........                                                                                  [ 88%]
kadi/tests/test_occweb.py ......................                                                                      [100%]

======================================== 197 passed, 2 xfailed in 104.52s (0:01:44) =========================================

Independent check of unit tests by [REVIEWER NAME]

• [PLATFORM]:

Functional tests

cd docs
make html  # No warnings
open _build/html/index.html  # looks OK

[javierggt]

I went over the changes and they make sense to me. I also made the documentation locally and the differences seem small.