[perf] deleteShapes (#1373)

This PR extracts a static query for the page states that are used when
deleting a shape.

### Change Type

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- [x] `patch` — Bug Fix

### Release Notes

- Perf improvement for deleting shapes in a document with lots of pages.

packages/editor/src/lib/app/App.ts

@@ -1296,6 +1296,10 @@ export class App extends EventEmitter<TLEventMap> {
 	// 	const update = this.getShapeUtil(next).onUpdate?.(prev, next)
 	// 	return update ?? next
 	// }
+	@computed
+	private get _allPageStates() {
+		return this.store.query.records('instance_page_state')
+	}
 
 	/** @internal */
 	private _shapeWillBeDeleted(deletedShape: TLShape) {
@@ -1312,8 +1316,8 @@ export class App extends EventEmitter<TLEventMap> {
 				this._unbindArrowTerminal(arrow, handleId)
 			}
 		}
+		const pageStates = this._allPageStates.value
 
-		const pageStates = this.store.query.records('instance_page_state').value
 		const deletedIds = new Set([deletedShape.id])
 		const updates = compact(
 			pageStates.map((pageState) => {