feat(core): enable new all docs by default (#12404)

<!-- This is an auto-generated comment: release notes by coderabbit.ai -->
## Summary by CodeRabbit

- **Refactor**
  - Simplified the user interface by always displaying the new All Pages view, removing the feature flag and old page version.
  - Updated selection interactions to use shift+click on document items instead of checkboxes.
  - Centralized drag-and-drop functionality in document list items and simplified drag handle behavior.
  - Generalized new page button component to accept standard HTML attributes.
  - Changed test ID attributes on new page buttons and list headers to use standard `data-testid`.

- **Bug Fixes**
  - Added stable test identifiers to new page buttons, document list items, menu items, and operation buttons for improved test reliability.
  - Enabled external drag-and-drop support on the trash button.

- **Tests**
  - Streamlined and updated end-to-end tests to match the new selection flow and UI changes, removing outdated or redundant test cases.
  - Simplified utility functions and wait conditions in test helpers for better accuracy and maintainability.
  - Updated selectors in tests to reflect new document item identifiers and centralized page element retrieval using utility functions.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

packages/frontend/core/src/desktop/pages/workspace/all-page/all-page-header.tsx

@@ -104,6 +104,7 @@ export const AllDocsHeader = ({
           onCreatePage={e => createPage('page', { at: inferOpenMode(e) })}
           onCreateDoc={e => createPage(undefined, { at: inferOpenMode(e) })}
           onImportFile={onImportFile}
+          data-testid="new-page-button-trigger"
         >
           <span className={styles.newPageButtonLabel}>{t['New Page']()}</span>
         </PageListNewPageButton>

packages/frontend/core/src/desktop/pages/workspace/all-page/all-page.tsx

@@ -12,7 +12,6 @@ import {
 } from '@affine/core/modules/collection';
 import { CollectionRulesService } from '@affine/core/modules/collection-rules';
 import type { FilterParams } from '@affine/core/modules/collection-rules/types';
-import { FeatureFlagService } from '@affine/core/modules/feature-flag';
 import { WorkspaceLocalState } from '@affine/core/modules/workspace';
 import { useI18n } from '@affine/i18n';
 import { useLiveData, useService } from '@toeverything/infra';
@@ -24,7 +23,6 @@ import {
   ViewIcon,
   ViewTitle,
 } from '../../../../modules/workbench';
-import { AllPage as AllPageOld } from '../all-page-old/all-page';
 import { AllDocSidebarTabs } from '../layouts/all-doc-sidebar-tabs';
 import * as styles from './all-page.css';
 import { AllDocsHeader } from './all-page-header';
@@ -350,10 +348,5 @@ export const AllPage = () => {
 };
 
 export const Component = () => {
-  const featureFlagService = useService(FeatureFlagService);
-  const enableNewAllDocsPage = useLiveData(
-    featureFlagService.flags.enable_new_all_docs_page.$
-  );
-
-  return enableNewAllDocsPage ? <AllPage /> : <AllPageOld />;
+  return <AllPage />;
 };

packages/frontend/core/src/desktop/pages/workspace/collection/list-header.tsx

@@ -100,7 +100,7 @@ export const CollectionListHeader = ({
         <Button onClick={handleEdit}>{t['Edit']()}</Button>
         <PageListNewPageButton
           size="small"
-          testId="new-page-button-trigger"
+          data-testid="new-page-button-trigger"
           onCreateDoc={onCreateDoc}
           onCreateEdgeless={onCreateEdgeless}
           onCreatePage={onCreatePage}