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/core/commands/CompoundCommand.ts

@@ -2,9 +2,8 @@ import type { Project } from '../model/Project';
 import type { Command } from './Command';
 
 /**
- * Several commands as one undo step (moving a multi-selection, for instance). Executes in
- * order; if one of them throws, the ones already done are rolled back before re-throwing,
- * so the project is never left half-changed.
+ * Several commands as one undo step. If one throws, the ones already done are rolled back before
+ * re-throwing, so the project is never left half-changed.
  */
 export class CompoundCommand implements Command {
   constructor(