chore: merge blocksuite source code (#9213)

blocksuite/playground/apps/starter/data/empty.ts

@@ -0,0 +1,28 @@
+import { type DocCollection, Text } from '@blocksuite/store';
+
+import type { InitFn } from './utils.js';
+
+export const empty: InitFn = (collection: DocCollection, id: string) => {
+  const doc = collection.getDoc(id) ?? collection.createDoc({ id });
+  doc.clear();
+
+  doc.load(() => {
+    // Add root block and surface block at root level
+    const rootId = doc.addBlock('affine:page', {
+      title: new Text(),
+    });
+
+    doc.addBlock('affine:surface', {}, rootId);
+
+    // Add note block inside root block
+    const noteId = doc.addBlock('affine:note', {}, rootId);
+    // Add paragraph block inside note block
+    doc.addBlock('affine:paragraph', {}, noteId);
+  });
+
+  doc.resetHistory();
+};
+
+empty.id = 'empty';
+empty.displayName = 'Empty Editor';
+empty.description = 'Start from empty editor';