Split the object inspector, and sweep out the section banners

objectSection.ts had grown to 559 lines around three separable parts: the
queries, the vector rows and the parent row. Four object commands repeated the
same capture/restore preamble – applyCommands stays out, its five carry extra
undo state whose restore order matters.

58 dashed banner comments are gone. The nine labels in nodes/index.ts stay:
they are the only structure a flat 90-entry array has.

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

src/editor/inspector/objectSection.ts

@@ -5,7 +5,6 @@ import {
   RevertOverrideToTemplateCommand,
   RevertPositionToTemplateCommand,
 } from '../../core/commands/applyCommands';
-import type { Command } from '../../core/commands/Command';
 import { UnpackContainerCommand } from '../../core/commands/containerCommands';
 import {
   ClearOverrideCommand,
@@ -13,21 +12,18 @@ import {
   RenameSceneObjectCommand,
   SetEditorOffsetCommand,
   SetOverrideCommand,
-  SetParentCommand,
 } from '../../core/commands/sceneObjectCommands';
 import type { Asset } from '../../core/model/Asset';
-import { findObject, isSelfOrAncestor, treeOrder } from '../../core/model/hierarchy';
+import { findObject } from '../../core/model/hierarchy';
 import {
   type InstanceTarget,
-  instanceTargetOf,
   isLiveInstance,
   isTemplateContent,
-  objectRef,
   type ObjectRef,
   resolvedHolder,
 } from '../../core/model/instance';
-import type { Axis, PropertyBag, PropertyValue } from '../../core/model/Properties';
-import { findAsset, findObjectHolder, type ObjectHolder, type Project } from '../../core/model/Project';
+import type { PropertyValue } from '../../core/model/Properties';
+import { findAsset, findObjectHolder, type Project } from '../../core/model/Project';
 import type { SceneObject } from '../../core/model/SceneObject';
 import {
   COMMON_PROPS,
@@ -41,28 +37,15 @@ import {
   deviatesFromTemplate,
   resolveSceneObjectProps,
 } from '../../core/properties/resolve';
-import { Button, Dropdown, Label, Menu, type MenuItem, TextField } from '../../ui';
+import { Button, TextField } from '../../ui';
 import { addCollider, createContainer, removeObjects } from '../actions';
 import { aspectActions, sizeCommand } from './aspectAction';
-import { createFieldRow, type FieldActions, type FieldRow, labelledRow } from './fieldFactory';
+import { createFieldRow, type FieldRow, labelledRow } from './fieldFactory';
 import { addGap, addNote, addTitle, type InspectorHost } from './host';
+import { parentRow } from './parentRow';
 import { previewingHandlers } from './previewHandlers';
-
-const POSITION_AXES: readonly Axis[] = ['x', 'y', 'z'];
-const OFFSET_AXES = ['x', 'y'] as const;
-
-const offsetKey = (axis: 'x' | 'y') => `editorOffset${axis.toUpperCase()}`;
-
-/** The holder with the content of placed containers resolved in – what the inspector addresses. */
-function viewOf(project: Project, holderId: string): ObjectHolder | undefined {
-  const holder = findObjectHolder(project, holderId);
-  return holder && resolvedHolder(project, holder);
-}
-
-function targetOf(project: Project, holderId: string, objectId: string): InstanceTarget | undefined {
-  const holder = findObjectHolder(project, holderId);
-  return holder && instanceTargetOf(project, holder, objectId);
-}
+import { currentProps, currentRef, deviations, positionMoved, targetOf, viewOf } from './objectQueries';
+import { componentRow, OFFSET_AXES, offsetKey, POSITION_AXES } from './vectorRows';
 
 /** Structure-defining facts of an object selection: parent, template link and schema. */
 export function objectSignature(
@@ -124,7 +107,6 @@ export function buildObjectsSection(host: InspectorHost, holderId: string, objec
   );
 }
 
-/** One object: name, asset, parent, container link, the switch, position, editor offset, properties, collider button. */
 export function buildObjectSection(host: InspectorHost, holderId: string, objectId: string): void {
   const { project } = host.state;
   const view = viewOf(project, holderId);
@@ -311,48 +293,6 @@ export function refreshObjectSection(host: InspectorHost, holderId: string, obje
   return true;
 }
 
-interface ComponentSpec<V extends object> {
-  key: string;
-  label: string;
-  axis: keyof V & string;
-  read: (ref: ObjectRef) => V;
-  write: (ref: ObjectRef, value: V) => void;
-  command: (value: V) => Command;
-  reset?: FieldActions;
-  apply?: FieldActions;
-}
-
-/**
- * A number row editing one component of a vector on the object (position, editor offset).
- * The row edits one axis, the command carries the whole vector: the other components come
- * from the target after the preview was taken back, so they are the pre-preview ones.
- */
-function componentRow<V extends object>(
-  host: InspectorHost,
-  holderId: string,
-  objectId: string,
-  value: number,
-  spec: ComponentSpec<V>,
-): void {
-  const withAxis = (vector: V, next: PropertyValue): V => ({ ...vector, [spec.axis]: Number(next) });
-  const row = createFieldRow(
-    host,
-    { key: spec.key, label: spec.label, kind: 'number', default: 0, step: 1 },
-    value,
-    previewingHandlers<ObjectRef, V>(host, {
-      target: () => currentRef(host.state, holderId, objectId),
-      // Copied: the snapshot outlives the scrub, the vector in the model does not.
-      read: (ref) => ({ ...spec.read(ref) }),
-      write: spec.write,
-      toModel: (next, ref) => withAxis(spec.read(ref), next),
-      commit: spec.command,
-    }),
-    { reset: spec.reset, apply: spec.apply },
-  );
-  host.fields.set(spec.key, row);
-  host.body.add(row.row);
-}
-
 /**
  * One editable property of a placed object: writes an override, offers ↺ (back to the asset
  * or, inside a container, to the template) and ↑ (apply upwards).
@@ -444,43 +384,6 @@ function propertyRow(
   return row;
 }
 
-/**
- * "Parent: <name> ▾" – picks another object of the same scene or container, or none. The object's own
- * subtree is excluded (that would be a cycle). For behaviors the parent is the owner. Content of a
- * placed container only shows its parent: where it hangs is the template's business.
- */
-function parentRow(host: InspectorHost, holder: ObjectHolder, object: SceneObject, fixed: boolean) {
-  const { row } = labelledRow('Parent');
-  const nameOf = (o: SceneObject) => o.name || findAsset(host.state.project, o.assetId)?.name || '?';
-  const parent = findObject(holder, object.parentId);
-  const name = parent ? nameOf(parent) : 'None';
-  if (fixed) {
-    row.add(new Label(name, { style: 'muted' }), 1);
-    return row;
-  }
-  const button = new Dropdown(name);
-  button.onClick = () => {
-    // Resolved anew on every open: `holder` is a derived copy of the scene, so one captured when
-    // the row was built lists the objects of that moment, not the ones there now.
-    const current = viewOf(host.state.project, holder.id) ?? holder;
-    const items: MenuItem[] = [
-      { label: 'None', onSelect: () => host.state.execute(new SetParentCommand(holder.id, object.id, '')) },
-    ];
-    for (const { object: candidate, depth } of treeOrder(current)) {
-      if (isSelfOrAncestor(current, object.id, candidate.id)) continue;
-      const label = `${'   '.repeat(depth)}${nameOf(candidate)}`;
-      items.push({
-        label: candidate.id === object.parentId ? `● ${label}` : label,
-        onSelect: () => host.state.execute(new SetParentCommand(holder.id, object.id, candidate.id)),
-      });
-    }
-    // Searchable: this lists every object of the scene or container, which grows with the project.
-    new Menu(items, { searchable: true }).openBelow(button);
-  };
-  row.add(button, 1);
-  return row;
-}
-
 /**
  * Gold marks exactly what the ↺/↑ buttons offer: for content of a placed container a deviation
  * from the template (position per axis, overrides), for any other object one from the asset. The
@@ -505,55 +408,3 @@ function markObjectRows(
     host.fields.get(def.key)?.setModified(deviates);
   }
 }
-
-/**
- * What the ↺/↑ menus may offer, each only when it actually differs. Reset goes to the nearest base
- * only: dropping a deviation inside a container lands on the template, never past it. Evaluated on
- * demand so a menu never acts on a stale snapshot.
- */
-function deviations(
-  state: InspectorHost['state'],
-  holderId: string,
-  objectId: string,
-  key: string,
-): { template: boolean; asset: boolean; applyToAsset: boolean } {
-  const view = viewOf(state.project, holderId);
-  const object = view && findObject(view, objectId);
-  const asset = object && findAsset(state.project, object.assetId);
-  if (!view || !object || !asset) return { template: false, asset: false, applyToAsset: false };
-  const target = targetOf(state.project, holderId, objectId);
-  const fromAsset = deviatesFromAsset(object, asset, key);
-  return {
-    template: Boolean(target) && deviatesFromTemplate(object, target!.base, key),
-    asset: !target && fromAsset,
-    applyToAsset: fromAsset,
-  };
-}
-
-/** Whether the object sits somewhere else on `axis` than its container template says. */
-function positionMoved(
-  state: InspectorHost['state'],
-  holderId: string,
-  objectId: string,
-  axis: Axis,
-): boolean {
-  const target = targetOf(state.project, holderId, objectId);
-  const object = currentRef(state, holderId, objectId)?.object;
-  return Boolean(target && object) && object!.position[axis] !== target!.base.position[axis];
-}
-
-function currentRef(
-  state: InspectorHost['state'],
-  holderId: string,
-  objectId: string,
-): ObjectRef | undefined {
-  const holder = findObjectHolder(state.project, holderId);
-  return holder && objectRef(state.project, holder, objectId);
-}
-
-/** The values the object shows right now, asset defaults and overrides merged. */
-function currentProps(state: InspectorHost['state'], holderId: string, objectId: string): PropertyBag | null {
-  const object = currentRef(state, holderId, objectId)?.object;
-  const asset = object && findAsset(state.project, object.assetId);
-  return object && asset ? resolveSceneObjectProps(asset, object) : null;
-}