refactor(web): migrate document list query state to nuqs (#32339)

.agents/skills/frontend-testing/SKILL.md

@@ -204,6 +204,16 @@ When assigned to test a directory/path, test **ALL content** within that path:
 
 > See [Test Structure Template](#test-structure-template) for correct import/mock patterns.
 
+### `nuqs` Query State Testing (Required for URL State Hooks)
+
+When a component or hook uses `useQueryState` / `useQueryStates`:
+
+- ✅ Use `NuqsTestingAdapter` (prefer shared helpers in `web/test/nuqs-testing.tsx`)
+- ✅ Assert URL synchronization via `onUrlUpdate` (`searchParams`, `options.history`)
+- ✅ For custom parsers (`createParser`), keep `parse` and `serialize` bijective and add round-trip edge cases (`%2F`, `%25`, spaces, legacy encoded values)
+- ✅ Verify default-clearing behavior (default values should be removed from URL when applicable)
+- ⚠️ Only mock `nuqs` directly when URL behavior is explicitly out of scope for the test
+
 ## Core Principles
 
 ### 1. AAA Pattern (Arrange-Act-Assert)

.agents/skills/frontend-testing/references/checklist.md

@@ -80,6 +80,9 @@ Use this checklist when generating or reviewing tests for Dify frontend componen
 - [ ] Router mocks match actual Next.js API
 - [ ] Mocks reflect actual component conditional behavior
 - [ ] Only mock: API services, complex context providers, third-party libs
+- [ ] For `nuqs` URL-state tests, wrap with `NuqsTestingAdapter` (prefer `web/test/nuqs-testing.tsx`)
+- [ ] For `nuqs` URL-state tests, assert `onUrlUpdate` payload (`searchParams`, `options.history`)
+- [ ] If custom `nuqs` parser exists, add round-trip tests for encoded edge cases (`%2F`, `%25`, spaces, legacy encoded values)
 
 ### Queries
 

.agents/skills/frontend-testing/references/mocking.md

@@ -125,6 +125,31 @@ describe('Component', () => {
 })
 ```
 
+### 2.1 `nuqs` Query State (Preferred: Testing Adapter)
+
+For tests that validate URL query behavior, use `NuqsTestingAdapter` instead of mocking `nuqs` directly.
+
+```typescript
+import { renderHookWithNuqs } from '@/test/nuqs-testing'
+
+it('should sync query to URL with push history', async () => {
+  const { result, onUrlUpdate } = renderHookWithNuqs(() => useMyQueryState(), {
+    searchParams: '?page=1',
+  })
+
+  act(() => {
+    result.current.setQuery({ page: 2 })
+  })
+
+  await waitFor(() => expect(onUrlUpdate).toHaveBeenCalled())
+  const update = onUrlUpdate.mock.calls[onUrlUpdate.mock.calls.length - 1][0]
+  expect(update.options.history).toBe('push')
+  expect(update.searchParams.get('page')).toBe('2')
+})
+```
+
+Use direct `vi.mock('nuqs')` only when URL synchronization is intentionally out of scope.
+
 ### 3. Portal Components (with Shared State)
 
 ```typescript