HSL: click a colour chip to open its panel, the way PICK does

The colour band chips only aimed the mixer before; now they open the same
panel the eyedropper opens, seeded with the colour the chip is named after
(hexToRgb turns that readout back into the RGB bytes the picker stores).
A pick already on the photo keeps its spot — only a mixer with nowhere to
hang takes the middle of the frame.

The HSL column itself is untouched: 8 chips, the rule, IMAGE,
HUE/SAT/LUM, the readout and RESET all stay where they were.

docker/frontend/src/ui/ChipColumn.tsx

@@ -99,7 +99,12 @@ export function ChipRow({ chips, grid }: { chips: ChipDef[]; grid?: boolean }) {
             }}
           >
             {chip.color ? <span className="chip-dot" data-color={chip.color} style={{ background: chip.color }} /> : null}
-            {chip.label}
+            {/* The name is a box, not the bare text node it used to be: a flex
+                container turns a loose text node into an anonymous item of its
+                own, and on iOS that item stops being painted until the column
+                it sits in is touched. Same fault, same shape as the panel head
+                (see `dev-panel-label` in DevelopPanels). No rule of its own. */}
+            <span className="chip-label">{chip.label}</span>
             {chip.value ? <span className="val">{chip.value}</span> : null}
             {chip.pro ? <span className="pro">PRO</span> : null}
           </button>