Minor documentation improvements

[ajstewart]

Includes the following improvements:

• Epoch Based Beamwidth Limit Clarification Somehow I had missed adding clarification on the behaviour of the initial on-sky separation limit during de Ruiter association when epoch based association is used. I felt sure I had but I couldn't find it!
• Dark Mode Enabled a dark mode for the docs.
• .env File information Added some details about the settings in the .env file as I thought this was lacking.
• Clarified Django Q Just to make a bit clearer that it is needed for running jobs via the website.
• VAST Icon Created VAST logo in an icon resolution so it doesn't appear stretched.

[marxide]

Looks good! I love the dark mode, but since it's unlabelled I only knew it was there because you mentioned it to me earlier. I wonder if changing the icon to the weather-sunny and weather-night icons would be better than the current toggle switch? Just a thought, I don't feel very strongly about it.

[ajstewart]

Looks good! I love the dark mode, but since it's unlabelled I only knew it was there because you mentioned it to me earlier. I wonder if changing the icon to the weather-sunny and weather-night icons would be better than the current toggle switch? Just a thought, I don't feel very strongly about it.

This did cross my mind, I guess I have used so many dark modes now that I would be expecting that toggle to switch modes, there is also the hover info:

The toggle is the default, the bundled options are:

I do like the toggle as I like the minimalist approach, but I'd probably vote for the lightbulbs if we wanted more of a graphical representation? Though like you, I don't have that strong feelings on it.

[ajstewart]

@marxide 7389173 bumps mkdocs-material to 7.1.1 minimum as I noticed dark mode wasn't working when I was on a lower version.

I had a look to see what the other icons looked like but I still vote for the toggle in the end, simple because in my opinion, the icon indicates that it's something that can be toggled where as the other images don't really indicate that it's something that can be clicked.