Includes zoom to selection, and pan to selection (which
centres the result but doesn't change the zoom).
I'm not sure this is the perfect solution to search pane
settings, but it's near to the action, but not taking up
too much space, doesn't need to open a modal to mess
with it, and has room for more options in future.
I haven't made toggling these options into full-blown
TOOL_ACTIONs, but they could be if a hotkey to toggle
these is desirable - it's an ACTION_MENU, so it should
just slot in..
Fixes: https://gitlab.com/kicad/code/kicad/-/issues/16192
Some of these are due to moving to wxWidgets 3.2, but I'm not sure
all of them are. In particular, the need for CallAfter() in the
search pane's selection handler is probably just a wxWidgets bug on
Mac (the control lies about the current selection inside the event
handler).
Also sets better column widths in the search pane.
