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/ui/KeyboardBridge.ts

@@ -1,17 +1,15 @@
 /**
- * The one piece of DOM in the whole application: an invisible, off-screen `<input>` that
- * receives keyboard focus while a canvas text field is being edited. The browser supplies
- * IME composition, the mobile on-screen keyboard, clipboard and selection semantics; the
- * canvas field mirrors `value` / selection from here. Nothing visible is DOM.
+ * The one piece of DOM in the application: an invisible `<input>` that holds keyboard focus while
+ * a canvas text field is edited, so the browser supplies IME, clipboard, selection and the mobile
+ * keyboard. The canvas field mirrors its value and selection.
  */
 
-/** A canvas text field while it is being edited; the bridge forwards the input's events to it. */
 export interface TextEditTarget {
   /** Called whenever value or selection changed. */
   onBridgeInput(value: string, selectionStart: number, selectionEnd: number): void;
   /** Called for navigation keys (Enter, Escape, Tab, arrows …). Return true to consume. */
   onBridgeKey(event: KeyboardEvent): boolean;
-  /** The bridge lost DOM focus (user clicked elsewhere, window blur). */
+  /** The bridge lost DOM focus. */
   onBridgeBlur(): void;
 }
 
@@ -65,7 +63,7 @@ export class KeyboardBridge {
     });
   }
 
-  /** Start editing: mirror the field's value into the input and grab DOM focus. */
+  /** Mirrors the field's value into the input and grabs DOM focus. */
   attach(
     target: TextEditTarget,
     value: string,
@@ -86,21 +84,18 @@ export class KeyboardBridge {
     this.input.style.top = `${Math.max(0, y)}px`;
   }
 
-  /**
-   * Push a value/selection the canvas side changed (arrow stepping, caret placement) into the
-   * input, so the next keystroke edits the same text the user sees.
-   */
+  /** Pushes a value the canvas side changed into the input, so the next keystroke edits that text. */
   setValue(value: string, selectionStart = value.length, selectionEnd = selectionStart): void {
     this.input.value = value;
     if (document.activeElement === this.input) this.input.setSelectionRange(selectionStart, selectionEnd);
   }
 
-  /** Selects the whole input; the field learns about it through the usual `onBridgeInput` sync. */
+  /** The field learns about it through the usual `onBridgeInput` sync. */
   selectAll(): void {
     this.input.select();
   }
 
-  /** Stop editing for `target`. Ignored when another field attached meanwhile, so a late blur cannot steal it. */
+  /** Ignored when another field attached meanwhile, so a late blur cannot steal it. */
   detach(target: TextEditTarget): void {
     if (this.target !== target) return;
     this.target = null;