feat(note): add topic recent-update endpoint and api-client method

Returns max(modified, created) across published notes of a topic.
Frontends previously inferred this from the latest note (size=1) which
broke when modified was null on most notes.

Author: Innei

apps/core/src/modules/note/note.controller.ts

@@ -722,6 +722,18 @@ export class NoteController {
     return result
   }
 
+  @Get('/topics/:id/recent-update')
+  async getTopicRecentUpdate(
+    @Param() params: MongoIdDto,
+    @HasAdminAccess() isAuthenticated: boolean,
+  ) {
+    const ts = await this.noteService.getTopicRecentUpdate(
+      params.id,
+      isAuthenticated,
+    )
+    return { ts }
+  }
+
   @Patch('/:id/publish')
   @Auth()
   async setPublishStatus(

apps/core/src/modules/note/note.service.ts

@@ -604,4 +604,21 @@ export class NoteService {
       },
     )
   }
+
+  async getTopicRecentUpdate(
+    topicId: string,
+    isAuthenticated: boolean,
+  ): Promise<Date | null> {
+    const objectId = new this.model.base.Types.ObjectId(topicId)
+    const match: Record<string, unknown> = { topicId: objectId }
+    if (!isAuthenticated) match.isPublished = true
+
+    const [doc] = await this.model.aggregate<{ ts: Date }>([
+      { $match: match },
+      { $project: { ts: { $ifNull: ['$modified', '$created'] } } },
+      { $sort: { ts: -1 } },
+      { $limit: 1 },
+    ])
+    return doc?.ts ?? null
+  }
 }

packages/api-client/__tests__/controllers/note.test.ts

@@ -1,9 +1,10 @@
+import { vi } from 'vitest'
+
 import { mockRequestInstance } from '~/__tests__/helpers/instance'
 import { mockResponse } from '~/__tests__/helpers/response'
 import { axiosAdaptor } from '~/adaptors/axios'
 import { NoteController } from '~/controllers'
 import { RequestError } from '~/core'
-import { vi } from 'vitest'
 
 const { spyOn } = vi
 
@@ -119,4 +120,14 @@ describe('test note client', () => {
 
     expect(data).toEqual({ data: [], pagination: {} })
   })
+
+  test('GET /notes/topics/:id/recent-update', async () => {
+    mockResponse('/notes/topics/11111111/recent-update', {
+      ts: '2025-10-19T14:57:30.803Z',
+    })
+
+    const data = await client.note.getTopicRecentUpdate('11111111')
+
+    expect(data).toEqual({ ts: '2025-10-19T14:57:30.803Z' })
+  })
 })

packages/api-client/controllers/note.ts

@@ -213,4 +213,14 @@ export class NoteController<ResponseWrapper> implements IController {
       params: { page, size, lang, ...sortOptions },
     })
   }
+
+  /**
+   * 获取专栏的最近更新时间（取该专栏下所有可见日记 max(modified, created)）
+   * @param topicId 专栏 ID
+   */
+  getTopicRecentUpdate(topicId: string) {
+    return this.proxy.topics(topicId)['recent-update'].get<{
+      ts: string | null
+    }>()
+  }
 }