test(temporary-notes): cover the create race-guard, broadcast deadline + cache patch; unify page->tree-node mappers

Address review comment 2159 on the temporary-notes UI work.

Tests:
- tree-model: cover handleCreate's race-guard temporaryExpiresAt patch — (a)
  server node inserted WITHOUT a deadline + create response carries one => node
  gains the deadline; (b) node already has a deadline => not overwritten, prev
  returned by reference.
- ws-tree.service.spec: broadcastPageCreated now asserts the deadline is carried
  when present and pinned to null (`?? null`) when absent.
- page-embed-query (new spec): syncTemporaryExpiresInCache patches the in-tree
  node's temporaryExpiresAt, and leaves the atom value at the same reference when
  the id is absent from the loaded tree (no write).

Refactor (closes the drift bug-class at the root):
- Client: extract one canonical pageToTreeNode(page, overrides) mapper in
  tree/utils and route buildTree, handleCreate's optimistic insert, the restore
  mutation and the duplicate handler through it. Restore stays permanent (server
  nulls temporaryExpiresAt) and duplicate stays permanent (server arms no timer)
  — both now reflect the server without a reload, where before they dropped the
  field entirely.
- Server: extract one toTreeNodeSnapshot(page) helper called by both the
  PAGE_CREATED event enrichment (page.repo) and the addTreeNode broadcast
  (ws-tree.service), so the optional temporaryExpiresAt can't drift between the
  two literals.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

apps/server/src/database/listeners/page.listener.ts

@@ -28,6 +28,36 @@ export interface TreeNodeSnapshot {
   temporaryExpiresAt?: Date | string | null;
 }
 
+/**
+ * Single canonical builder for a `TreeNodeSnapshot` from a page-like row. Both
+ * the `PAGE_CREATED` event enrichment (`page.repo.insertPage`) and the
+ * `addTreeNode` broadcast (`WsTreeService.broadcastPageCreated`) build this same
+ * snapshot; routing both through here keeps the optional `temporaryExpiresAt`
+ * (and the `?? null` normalisation that pins a permanent note to an explicit
+ * null) from silently drifting between the two literals.
+ */
+export function toTreeNodeSnapshot(page: {
+  id: string;
+  slugId: string;
+  title: string | null;
+  icon: string | null;
+  position: string;
+  spaceId: string;
+  parentPageId: string | null;
+  temporaryExpiresAt?: Date | string | null;
+}): TreeNodeSnapshot {
+  return {
+    id: page.id,
+    slugId: page.slugId,
+    title: page.title,
+    icon: page.icon,
+    position: page.position,
+    spaceId: page.spaceId,
+    parentPageId: page.parentPageId,
+    temporaryExpiresAt: page.temporaryExpiresAt ?? null,
+  };
+}
+
 export class PageEvent {
   pageIds: string[];
   workspaceId: string;

apps/server/src/database/repos/page/page.repo.ts

@@ -16,7 +16,10 @@ import { jsonArrayFrom, jsonObjectFrom } from 'kysely/helpers/postgres';
 import { SpaceMemberRepo } from '@docmost/db/repos/space/space-member.repo';
 import { EventEmitter2 } from '@nestjs/event-emitter';
 import { EventName } from '../../../common/events/event.contants';
-import { TreeUpdateSnapshot } from '../../listeners/page.listener';
+import {
+  TreeUpdateSnapshot,
+  toTreeNodeSnapshot,
+} from '../../listeners/page.listener';
 
 /**
  * Optional extras for the PAGE_UPDATED event emitted by updatePage(s). Lets the
@@ -200,20 +203,10 @@ export class PageRepo {
     this.eventEmitter.emit(EventName.PAGE_CREATED, {
       pageIds: [result.id],
       workspaceId: result.workspaceId,
-      pages: [
-        {
-          id: result.id,
-          slugId: result.slugId,
-          title: result.title,
-          icon: result.icon,
-          position: result.position,
-          spaceId: result.spaceId,
-          parentPageId: result.parentPageId,
-          // Carry the death-timer deadline so a note created as temporary shows
-          // its sidebar clock marker on every client without a reload.
-          temporaryExpiresAt: result.temporaryExpiresAt,
-        },
-      ],
+      // Built via the shared snapshot helper so the field copy (and the
+      // death-timer deadline that shows the sidebar clock marker without a
+      // reload) can't drift from the `addTreeNode` broadcast literal.
+      pages: [toTreeNodeSnapshot(result)],
     });
 
     return result;