UI.15 Theme-coloured icons, and the colorize colour carried to labels and eyebrows

Settings › Global › Icons offers Full colour (fixed pastel fills: --ic-a #8fd3f5, --ic-b #ffb870, …, the same on light and dark), Outline colorized (one colour the person picks, --cc-icon-color) and Each app's own drawings. Owner: "cleaner colorful and theme colored icons (see color, colorize setting of icons - labels/eyebrows should follow)". Change: (1) a Theme colour style: the fills and accent lines derived from the theme tokens at render time (the app's layer colour --layer-<app> for the accent s1, its complement for s2, fills as tints of the sheet toward the layer colour with the ink as the line), so icons follow light / dark and change with the app, and a "Colour" pick (app colour, a layer colour, or any colour) under it; (2) the Full colour fills get a dark-theme set (today the same pastels sit on #1D232B and look washed); (3) "Labels and eyebrows follow": a switch that gives group titles (the ribbon's group names, the tool rows' group labels, palette headers, tab labels, the status bar's section names) the icon colour too, finishing FX.91 (group names in the app's colour, partial) with one rule for every block; disabled stays plainly grey (FX.90) in every style; (4) a contrast check in Settings: the picked colour is shown against both sheets and a warning says when it fails 3:1 on either. CSS stays token-only (--ic-* in app-workspace.css); the icon module reads the theme once and on the cc-space change.