Add advanced settings checkbox and hide advanced settings by default

[grorp]

Based on #13730, this PR adds a "Show advanced settings" checkbox to the new settings GUI. As discussed, the checkbox determines whether the "Advanced" and "Mapgen" toplevel categories are shown and is unchecked by default.

This is part of #13476 "Before 5.8.0". The creation of this PR was discussed on IRC: https://irc.minetest.net/minetest-dev/2023-10-01#i_6118939.

To do

This PR is a Ready for Review.

How to test

Open the settings and toggle the "Show advanced settings" checkbox. Verify that it changes the visibility of the "Advanced" and "Mapgen" toplevel categories, and nothing else.

Verify that you don't stay on an advanced settings page if you uncheck the checkbox while you are on an advanced settings page.

Verify that toggling the checkbox doesn't reset the current page and scroll position in other cases.

[SmallJoker]

Works. The scrollbar is also reasonably positioned when toggling the state.
Unfortunately there is no visual indicator to mark which pages are affected by this checkbox (an idea for later).

[rubenwardy]

Looks good and works great. My only suggestion would be to make "Client and Server" advanced as well

[grorp]

My only suggestion would be to make "Client and Server" advanced as well

Seems reasonable.

There are now some advanced settings in the non-advanced sections (e.g. 3d_mode, enable_bloom_debug, water_wave_height, etc.) and some non-advanced settings in the advanced sections (e.g. client_mesh_chunk), but that can be cleaned up by a later PR.

[rubenwardy]

Works well