feat(dashboard): 最近动态改服务端分页

工作台「最近动态」原为聚合端点内嵌、固定截断前 20 条，操作日志变长后
既撑大响应又只能看到头部。改为独立分页端点：
- GET /api/v1/dashboard/activities，支持 pageNum/pageSize/module 筛选
- 模块筛选项与列表同源返回（全量模块名，不随翻页变化），前端不必再取一次全量
- 聚合端点去掉内嵌 activities，避免同一份数据两处查询

前端改用 usePagedList + 统一 AppPagination（每页 10/20/50），模块筛选由
本地过滤改为服务端筛选。集成测试 13 例（含翻页不重不漏 / 模块筛选 / 越权 403）。

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

backend/tests/integration/test_dashboard.py

@@ -118,10 +118,20 @@ def _dashboard(client: TestClient, headers: dict, month: str | None = None) -> d
     return resp.json()["data"]
 
 
+def _activities(client: TestClient, headers: dict, **params) -> dict:
+    """最近动态分页端点。"""
+    resp = client.get(f"{_DASHBOARD}/activities", params=params, headers=headers)
+    assert resp.status_code == 200, resp.text
+    return resp.json()["data"]
+
+
 def test_权限_普通用户403文案(client: TestClient, normal: dict):
     resp = client.get(_DASHBOARD, headers=normal["headers"])
     assert resp.status_code == 403
     assert resp.json()["message"] == "无权访问工作台"
+    # 最近动态分页端点同属工作台，权限一致
+    resp = client.get(f"{_DASHBOARD}/activities", headers=normal["headers"])
+    assert resp.status_code == 403
 
 
 def test_总览_绩效合计与台账一致且非法月份400(client: TestClient, admin: dict):
@@ -221,9 +231,40 @@ def test_预警_审批超时命中且参数关闭后不产生(client: TestClient
 
 def test_动态_来源操作日志(client: TestClient, admin: dict):
     _chain(client, admin["headers"])
-    data = _dashboard(client, admin["headers"])
-    assert data["activities"], "工作台动态为空：写操作应产生操作日志"
-    assert {"module", "action", "summary", "create_time"} <= set(data["activities"][0])
+    data = _activities(client, admin["headers"])
+    assert data["list"], "工作台动态为空：写操作应产生操作日志"
+    assert {"module", "action", "summary", "create_time"} <= set(data["list"][0])
+
+
+def test_动态_分页翻页不重不漏(client: TestClient, admin: dict):
+    _chain(client, admin["headers"])
+    first = _activities(client, admin["headers"], pageNum=1, pageSize=2)
+    assert first["pageNum"] == 1
+    assert first["pageSize"] == 2
+    assert len(first["list"]) == 2
+    assert first["total"] >= 2
+
+    second = _activities(client, admin["headers"], pageNum=2, pageSize=2)
+    assert len(second["list"]) == 2
+    # 两页不重不漏（倒序取，按 id 倒排）
+    first_ids = {item["id"] for item in first["list"]}
+    second_ids = {item["id"] for item in second["list"]}
+    assert first_ids.isdisjoint(second_ids)
+    assert first["list"][0]["id"] > second["list"][0]["id"]
+
+
+def test_动态_模块筛选与筛选项(client: TestClient, admin: dict):
+    _chain(client, admin["headers"])
+    page = _activities(client, admin["headers"], pageSize=50)
+    assert page["modules"], "模块筛选项不应为空"
+    module = page["modules"][0]
+
+    filtered = _activities(client, admin["headers"], module=module, pageSize=50)
+    assert filtered["total"] >= 1
+    assert filtered["list"], "按模块筛选后应有数据"
+    assert all(item["module"] == module for item in filtered["list"])
+    # 筛选项不随筛选条件变化（下拉里始终是全量模块）
+    assert filtered["modules"] == page["modules"]
 
 
 # ==== 角色待办 / 预警阈值 / 趋势（2026-10-19 code-review 修复回归）====