rb: touch debug overlay, tweak scaling (#801)

## Link to GitHub Issue or related Pull Request, if one exists
n/a

## Description of change
Similar to #797, draw an overlay to debug touch issues for reflec beat.

For rb, we draw on the ImGui surface. Draw horizontal and vertical line
for triggered sensors, and also a bounding box if scaling is in use.

Make small tweaks to how scaling works.

## Testing
Verified volzza 2 / reflesia / 1st game (landscape KBR)

src/spice2x/launcher/options.h

@@ -265,6 +265,7 @@ namespace launcher {
             JubeatTouchAlgo,
             JubeatTouchDebug,
             JubeatTouchDebounce,
+            RBTouchDebug,
             spice2x_RBTouchScale,
             RBTouchSize,
             RBTouchPollRate,