feat(workspace): bring an extracted note back into the bullet

A bullet that is only a link to a note (as left by /extract) gets a
"Notiz zurückholen" button. POST /documents/{id}/inline returns the
linked note's blocks with fresh ids and trashes the note; the editor
puts the title back as text and inserts the blocks as an own edit, so
Strg+Z restores the link and the note. Only own notes that no other
note links to. Release 0.52.0.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

frontend/src/lib/api.ts

@@ -799,6 +799,11 @@ export const api = {
     });
   },
 
+  /** The way back from extractBranch: the linked note's blocks for the bullet; the note goes to the trash. */
+  async inlineNote(docId: string, blockId: string): Promise<{ sourceId: string; content: string; blocks: DocumentBlock[] }> {
+    return request(`/api/v1/documents/${docId}/inline`, { method: 'POST', body: JSON.stringify({ blockId }) });
+  },
+
   /** Puts a note created by extractBranch into the trash again. */
   async undoExtract(newDocId: string): Promise<void> {
     await request(`/api/v1/documents/${newDocId}/extract/undo`, { method: 'POST' });