web: accent the brand and add the studio's quick gestures

- the brand "Cam", the avatar and the signed-in name follow the theme accent
- double-click a slider track resets that parameter; double-click the photo
  toggles 1:1 and the whole photo on the stage
- `*`, or a recipe chip dragged onto the star, files the look under FAVORITED
- RESET under CREATE clears the draft form, and the button now sits under a
  rule at the foot of the column

docker/frontend/src/ui/ChipColumn.tsx

@@ -14,6 +14,9 @@ export interface ChipDef {
   amberValue?: boolean;
   pro?: boolean;
   disabled?: boolean;
+  // Present when the chip itself can be dragged somewhere: the payload the drop
+  // target reads back (the recipe's id, for the FAVORITED rail button).
+  drag?: string;
   onClick: () => void;
 }
 
@@ -31,6 +34,8 @@ export interface SliderDef {
   // swatch under the ruler so the hue moves with the number. Absent = no swatch.
   swatch?: string;
   onChange: (value: number) => void;
+  // Double-clicking the track puts the parameter back to its default.
+  onReset: () => void;
   // "<" — closes the ruler and reopens the strip it was launched from.
   onBack: () => void;
 }
@@ -46,6 +51,15 @@ export function ChipRow({ chips }: { chips: ChipDef[] }) {
           className={`chip${chip.active ? ' on' : ''}${chip.amberValue ? ' amber' : ''}`}
           aria-pressed={!!chip.active}
           disabled={chip.disabled}
+          draggable={!!chip.drag}
+          onDragStart={
+            chip.drag
+              ? (e) => {
+                  e.dataTransfer.setData('text/plain', chip.drag!);
+                  e.dataTransfer.effectAllowed = 'copy';
+                }
+              : undefined
+          }
           onClick={chip.onClick}
         >
           {chip.label}
@@ -92,6 +106,7 @@ export function SliderRow({ slider }: { slider: SliderDef }) {
           step={slider.step}
           value={slider.value}
           onChange={(e) => slider.onChange(Number(e.target.value))}
+          onDoubleClick={slider.onReset}
         />
         {slider.swatch ? (
           <div