GUI: add inline colour picker control

Replace the six RGB sliders on the World tint card with a CK_COLOR control:
each row shows a live swatch and expands an inline picker with a
saturation/value square, a hue bar, and hex/RGB preview. The picker grows the
card in place so it scrolls/clips like any other row, keeps HSV state while
open (grey does not lose its hue), writes the shared 0-255 RGB triple used by
the config, and saves on mouse release.

Costs ~1.2k small rects per frame only while a picker is open; no texture
interface needed.

0 files changed, 0 insertions, 0 deletions