Trim needless comments and fix the picker width

Remove comments that only restate the code, keeping the section banners
and the notes that carry a reason, a measured fact or an external
contract.

ButtonOptions.width claimed to be a fixed width but only set minWidth,
so the Graph and Texture pickers grew with the name they showed. It is
now what it promises, with a separate minWidth for the buttons that have
two forms. Narrow buttons shrink their padding, otherwise a 24px icon
button had 8px left for its glyph and truncate dropped it entirely.

__gm.labelsDropped() guards that class: the overflow guard only saw text
that was too wide, never a label truncated to nothing.

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

src/editor/graph/GraphEditor.ts

@@ -9,12 +9,8 @@ import { GraphCanvas } from './GraphCanvas';
 const INFO_WIDTH = 150;
 
 /**
- * The Graph tab: a picker for which behavior is being worked on, the actions that act on the
- * whole graph, and the canvas the nodes are drawn on.
- *
- * It follows the selection – selecting a behavior asset, a placed behavior or one of its nodes
- * shows that graph – but it keeps showing the last behavior when the selection moves elsewhere.
- * Otherwise clicking a sprite to check its position would empty the graph you are editing.
+ * The Graph tab. It follows the selection, but keeps showing the last behavior when the
+ * selection moves elsewhere – clicking a sprite must not empty the graph being edited.
  */
 export class GraphEditor extends VStack {
   /** The canvas itself: the live redraw while playing and the check scripts reach for it. */
@@ -38,8 +34,7 @@ export class GraphEditor extends VStack {
     header.add(new Button('Fit', { onClick: () => this.canvas.fit() }));
     header.add(new Spacer(), 1);
     this.info = new Label('', { style: 'small', align: 'right' });
-    // Reserved rather than measured: the label is built empty, and a stack sizes it once from
-    // the text it had at the time – so without a floor the readout is clipped from then on.
+    // Reserved, not measured: a stack sizes the label once, from the empty text it was built with.
     this.info.minWidth = INFO_WIDTH;
     header.add(this.info);
 
@@ -63,6 +58,11 @@ export class GraphEditor extends VStack {
     return this.canvas.currentAssetId;
   }
 
+  /** For the check scripts: the picker's width must not follow the name it happens to show. */
+  get pickerWidth(): number {
+    return this.picker.w;
+  }
+
   private followSelection(): void {
     const id = this.state.selectedBehaviorId;
     // Null merely means "the selection is about something else"; the tab keeps its subject.
@@ -93,8 +93,7 @@ export class GraphEditor extends VStack {
   }
 
   private refresh(): void {
-    // A deleted behavior leaves the canvas empty; rather than showing nothing at all the tab
-    // falls back to whatever behavior is left, the way it starts out on the first one.
+    // A deleted behavior leaves the canvas empty; fall back to whatever behavior is left.
     if (!this.asset()) this.canvas.show(this.behaviors()[0]?.id ?? null);
     const asset = this.asset();
     this.picker.setText(asset ? asset.name : 'No behavior');