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  - Streamlined and updated end-to-end tests to match the new selection flow and UI changes, removing outdated or redundant test cases.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 -->

tests/affine-local/e2e/drag-page.spec.ts

@@ -106,7 +106,7 @@ test('drag a page from "All pages" list to favourites, then drag to trash', asyn
 
   const favouritePage = await dragToFavourites(
     page,
-    page.locator(`[data-testid="page-list-item"]:has-text("${title}")`),
+    page.locator(`[data-testid="doc-list-item"]:has-text("${title}")`),
     pageId
   );
 
@@ -124,7 +124,7 @@ test('drag a page from "All pages" list to collections, then drag to trash', asy
 
   const collectionPage = await dragToCollection(
     page,
-    page.locator(`[data-testid="page-list-item"]:has-text("${title}")`)
+    page.locator(`[data-testid="doc-list-item"]:has-text("${title}")`)
   );
 
   await dragToTrash(page, title, collectionPage);
@@ -140,7 +140,7 @@ test('drag a page from "All pages" list to trash', async ({ page }) => {
   await dragToTrash(
     page,
     title,
-    page.locator(`[data-testid="page-list-item"]:has-text("${title}")`)
+    page.locator(`[data-testid="doc-list-item"]:has-text("${title}")`)
   );
 });
 
@@ -155,7 +155,7 @@ test('drag a page from favourites to collection', async ({ page }) => {
   // drag to favourites
   const favouritePage = await dragToFavourites(
     page,
-    page.locator(`[data-testid="page-list-item"]:has-text("${title}")`),
+    page.locator(`[data-testid="doc-list-item"]:has-text("${title}")`),
     pageId
   );