docs: Adds basic documentation using mkdocs

[ns-rse]

I had an hour of work left and was unlikely to be able to concentrate deeply on work so used the time productively to
knock up the documentation for AFMReader using mkdocs.

Its pretty basic but once merged pushes to the main branch of files under docs/ will trigger the documentation to be
rebuilt. It includes the API docs auto-generated from docstrings and the ability to easily switch between versions.

This is a prelude to switching TopoStats and AFM-SPM.github.io over to
mkdocs.

If you want to test it out locally to see what it looks like...

git pull
git switch ns-rse/mkdocs-website
pip install -e .[docs]
mkdocs serve

...and check the output for the URL to view the site at locally.

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 72.00%. Comparing base (f282c31) to head (a01e030).
Report is 227 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #103      +/-   ##
==========================================
+ Coverage   65.87%   72.00%   +6.13%     
==========================================
  Files           3        8       +5     
  Lines         337      593     +256     
==========================================
+ Hits          222      427     +205     
- Misses        115      166      +51     

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[ns-rse]

No idea why markdownlint-cli2 is reporting these issues, the links are specified in a valid manner.

[ns-rse]

Ready for review.

Current pre-commit failure is not one we can get round I don't think as its a configuration option required for the rendering of the Mermaid diagram.

[Max-Gamill]

Yep looks good! Thanks for including my edits :)