Extend GraphicsOverrides with a mapOverlay group (territory highlight,
border highlight amount, border highlight thickness) and a railroad
group (train track draw distance), wired through the schema,
applyGraphicsOverrides, and new sliders in the graphics settings modal.
Fix the territory hover highlight: the shader received uHighlightBrighten
but ignored it, applying a hardcoded saturation boost so the setting had
no effect. It now drives a contrast boost (push channels away from
mid-gray), with 0 disabling the effect.
The train track slider is presented as a "draw distance" (inverted
railMinZoom) so higher = tracks stay visible when more zoomed out.
Also move the Graphics settings button to the top of the settings modal.
evanpelle
1c1728f6fa