Drop the collider and delete-node buttons from the inspector

Adding a collider now lives only in the Scene objects context menu, deleting a node on
the Delete key and the node context menu. The e2e checks that pinned the inspector button
now drive the hierarchy menu instead, including that its entry is disabled on template
content and on a placed container without raising a notice.

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

src/editor/inspector/objectSection.ts

@@ -38,7 +38,7 @@ import {
   resolveSceneObjectProps,
 } from '../../core/properties/resolve';
 import { Button, TextField } from '../../ui';
-import { addCollider, canAddCollider, createContainer, removeObjects } from '../actions';
+import { createContainer, removeObjects } from '../actions';
 import { aspectActions, sizeCommand } from './aspectAction';
 import { defSignature } from './assetSection';
 import { createFieldRow, type FieldRow, labelledRow, type RowActions } from './fieldFactory';
@@ -230,17 +230,6 @@ export function buildObjectSection(host: InspectorHost, holderId: string, object
   markObjectRows(host, object, asset, target);
 
   if (asset.type === 'container') contentSection(host, holderId, object, asset.objects.length);
-
-  const stored = findObjectHolder(project, holderId);
-  if (stored && canAddCollider(project, stored, object)) {
-    addGap(host);
-    host.body.add(
-      new Button('+ Add collider', {
-        variant: 'ghost',
-        onClick: () => addCollider(host.state, holderId, objectId),
-      }),
-    );
-  }
 }
 
 /**