The floating tone-curve card opened with its own row of channel tabs
(RGB / R / G / B) and a RESET button. The panel is meant to be a graph,
so that row is gone: the card is now the head and the curve, nothing
else. The curve edits the composite rgb channel, which is what the row
selected by default anyway.
- ToneCurvePanel.tsx: drop CURVE_CHANNELS, the channel state and the
curve-tabs block; every read and write goes through 'rgb'.
- app.css: drop .curve-tabs / .curve-tab / .curve-dot / .curve-reset
and the .curve-line.ghost path that only drew the other channels.
skipped: selecting a channel other than the composite one, and RESET,
add when a channel chooser comes back on purpose.
3dtours
05c2380a8b