feat(editor): show doc title in page block (#9975)

Close [BS-2392](https://linear.app/affine-design/issue/BS-2392/page-block-需要显示文章title)

### What Changes
- Add `<doc-title>` to edgeless page block (a.k.a the first page visible note block)
- Refactors:
  - Move `<doc-title>` to `@blocksuite/affine-component`, but you can aslo import it from `@blocksuite/preset`
  - Extract `<edgeless-note-mask>` and `<edgeless-note-background>` from `<affine-edgeless-note>` to a seperate file
  - Rewrite styles of `<affine-edgeless-note>` with `@vanilla-extract/css`

https://github.com/user-attachments/assets/a0c03239-803e-4bfa-b30e-33b919213b12

packages/frontend/core/src/components/blocksuite/block-suite-editor/specs/custom/widgets/edgeless-note-header.tsx

@@ -171,7 +171,7 @@ export const EdgelessNoteHeader = ({ note }: { note: NoteBlockModel }) => {
   const flags = useService(FeatureFlagService).flags;
   const insidePeekView = useInsidePeekView();
 
-  if (!flags.enable_page_block_header) return null;
+  if (!flags.enable_page_block) return null;
 
   const isFirstVisibleNote =
     note.parent?.children.find(