Enrich documentation for model users

[ai-mindset]

In order to

a) make it easier for a non-NHP model expert to get up and running with the model,
b) for new model devs to find their way through and maintain the code more easily (better bus factor),

it'd be useful to expand the README documentation with more detailed information on model setup, model usage, most important modules to look out for, idiosyncrasies we should be aware of and so on.

[tomjemmett]

worth looking at the history for the readme file as some of those points were previously included, but were removed.

worth considering whether these steps should exist in the readme, in a wiki, or perhaps we should resurrect the built documentation (perhaps utilise github pages now this is no longer private?)

[tomjemmett]

see #37 (and #36)

[tomjemmett]

I am working on a branch to solve #37 using mkdocs. waiting for #501 to be merged.

I think that these requests would fit nicely into docs that are rendered via GitHub actions. The readme should then link out to that. We could give very rich details on how a user might go about setting things up etc, while keeping the readme on github as is

[StatsRhian]

Moving to https://github.com/orgs/The-Strategy-Unit/projects/8