Mostly in pretty good shape.

* the loading progress indicators don’t look right
* imgui layer doesn’t properly handle a ui_adaptor that is supposed to
hide all other ui
* a uilist that is reset doesn’t show any options
* no second column text is drawn
* uilist is now an imgui window with a title, so the "text" of the
list has been split into a title and a help text; most just have a
title with no help text
* maybe other things

…his smaller, we can refactor uilist in a different PR

There’s no need for it to be a method of cataimgui::window, since it
accesses no state on the window. This will allow callers that are not
derived classes.

This shouldn’t change the output except in the case where no wrapping
is actually happening. When width was zero, the input was not actually
being broken into lines at all, causing confusion later on.

This uilist is supposed to fill the screen, but for some reason it is
too short. Also, the title has a color tag in it; probably that should
be moved to the help text.

The uilist_impl derives from cataimgui::window, which creates and
manages the ui_adaptor for us.

It was purely aesthetic. All it did was tweak the border of the uilist
so that it blends more seamlessly with some other UI already on the
screen, which is now unnecessary.

Drawing the map needed more work than I expected. It traverses the map
in an odd order, causing it to be flipped or rotated 180° when printed
naively. Thus both the original and the new implementation for ImGui
calculate the position of each character and reposition the cursor for
each one.

Now actually measure the menu items to find their width, and size the
window reliably to fit without growing larger than the screen. (Will
need to be tweaked when I fix the title bar though.)

There are some niggling little bugs left that I am too tired to work
out at the moment.

ImGui already has stacks for those. Of course, it's still not working
perfectly.

and a bunch of useless commented–out code that we have replaced.

Actually clicking to select an item doesn’t work for unknown reasons,
however. It always selects the wrong item.

it must have been brought in by a transitive include

The selected menu item is now updated on hover, and the correct menu
item now is activated on click. Really all that was missing was that
parent.selected was not being updated.

oops, forgot about it again