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/model/Project.ts

@@ -2,7 +2,7 @@ import { schemaForAsset } from '../properties/PropertySchema';
 import { type Asset, type ContainerAsset, isSceneAsset, type SceneAsset } from './Asset';
 import type { SceneObject } from './SceneObject';
 
-/** Written into every document. Reserved for format migrations – the loader does not branch on it yet. */
+/** Reserved for format migrations – the loader does not branch on it yet. */
 export const PROJECT_FORMAT_VERSION = 1;
 
 export interface Project {
@@ -10,7 +10,7 @@ export interface Project {
   id: string;
   name: string;
   assets: Asset[];
-  /** Scene shown in the viewport and instantiated on Play. Empty string = none. */
+  /** Empty string = none. */
   activeSceneId: string;
 }
 
@@ -22,7 +22,6 @@ export function findAsset(project: Project, assetId: string): Asset | undefined
   return project.assets.find((a) => a.id === assetId);
 }
 
-/** The scene asset with that id – undefined for other asset types as well. */
 export function findScene(project: Project, sceneId: string): SceneAsset | undefined {
   const asset = findAsset(project, sceneId);
   return asset && isSceneAsset(asset) ? asset : undefined;
@@ -33,9 +32,8 @@ export function listScenes(project: Project): SceneAsset[] {
 }
 
 /**
- * Everything that holds placed objects. Container assets do so just like scenes: their
- * `objects` are the template a placed container is instantiated from. Anything that walks
- * "all placed objects" has to cover both, or it silently skips the templates.
+ * Everything that holds placed objects. A container's `objects` are a template, so anything
+ * walking "all placed objects" must cover both or it silently skips the templates.
  */
 export type ObjectHolder = SceneAsset | ContainerAsset;
 
@@ -48,7 +46,6 @@ export interface SceneObjectRef {
   object: SceneObject;
 }
 
-/** Objects of all scenes and container templates that satisfy `predicate`, each with its holder. */
 export function objectsWhere(
   project: Project,
   predicate: (object: SceneObject) => boolean,
@@ -65,28 +62,14 @@ export function findUsages(project: Project, assetId: string): SceneObjectRef[]
   return objectsWhere(project, (o) => o.assetId === assetId);
 }
 
-/** One place where an `asset`-kind property points at an asset. */
 export type PropertyUsage =
   | { on: 'asset'; asset: Asset; key: string }
   | { on: 'object'; holder: ObjectHolder; object: SceneObject; key: string };
 
 /**
- * Every property that references one of `ids`, on assets and on the overrides of placed
- * objects.
- *
- * This is the other half of "where is this asset used": `findUsages` finds assets that were
- * *placed*, which is meaningless for a texture – a texture is never placed, it is worn by
- * sprites through their `texture` property. Deleting one therefore has to count both, or it
- * reports "0 uses" for a picture that ten sprites are showing.
- *
- * Several ids rather than one because a texture is referenced by more than its own id: every
- * frame cut from it is a reference to the same picture (see `textureRefIds`). Deleting the
- * texture has to count the sprites wearing a frame of it too, or it under-reports exactly the
- * sheets that were sliced – the ones with the most users.
- *
- * A reference is deliberately left dangling rather than cleared when its target goes: a
- * dangling one resolves to "no picture" everywhere it is read, and it comes back by itself
- * when the delete is undone.
+ * The other half of "where is this asset used": a texture is never placed, it is worn through a
+ * sprite's `texture` property, so counting uses needs this as well as `findUsages`. Several ids
+ * because every frame cut from a texture is a reference to the same picture (see `textureRefIds`).
  */
 export function findPropertyUsages(project: Project, ids: string | readonly string[]): PropertyUsage[] {
   const wanted = new Set((typeof ids === 'string' ? [ids] : ids).filter(Boolean));