Route the widget hover cursor through the theme

Button, Checkbox, the color swatch and list rows took a hard-coded
'pointer'; they now read Theme.hoverCursor, which is 'default'.

Also adds the todo note for a breadcrumb when drilling into a
sub-behavior in the graph.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

src/ui/widgets/Button.ts

@@ -37,7 +37,7 @@ export class Button extends Widget {
     this.align = options.align ?? 'center';
     this.onClick = options.onClick;
     this.focusable = true;
-    this.cursor = 'pointer';
+    this.cursor = Theme.hoverCursor;
     this.minHeight = Theme.controlHeight;
     this.fixedWidth = options.width ?? 0;
     this.minWidth = this.fixedWidth || (options.minWidth ?? 0);

src/ui/widgets/Checkbox.ts

@@ -11,7 +11,7 @@ export class Checkbox extends Widget {
   constructor(public checked = false) {
     super();
     this.focusable = true;
-    this.cursor = 'pointer';
+    this.cursor = Theme.hoverCursor;
     this.minWidth = Theme.controlHeight;
     this.minHeight = Theme.controlHeight;
     this.addChild(this.box);

src/ui/widgets/ColorField.ts

@@ -101,7 +101,7 @@ export class ColorField extends Widget {
 class SwatchButton extends Widget {
   constructor(graphics: Graphics, onTap: () => void) {
     super();
-    this.cursor = 'pointer';
+    this.cursor = Theme.hoverCursor;
     this.minWidth = Theme.controlHeight;
     this.minHeight = Theme.controlHeight;
     this.addChild(graphics);

src/ui/widgets/ListRow.ts

@@ -23,7 +23,7 @@ export class ListRow extends Widget {
     private readonly chevronSlot: boolean,
   ) {
     super();
-    this.cursor = 'pointer';
+    this.cursor = Theme.hoverCursor;
     this.minHeight = height;
     if (item.overridden) this.labelText.style = textStyle('override');
     this.addChild(this.bg, this.labelText, this.hint);