feat: prompt returns answer to caller + commit on own header line

crates/server/src/api.rs

@@ -564,6 +564,9 @@ pub async fn prompt_user(
     })
     .await
     {
+        Ok(ClientMessage::PromptResponse { answer, .. }) => {
+            (StatusCode::OK, Json(serde_json::json!({ "ok": true, "answer": answer }))).into_response()
+        }
         Ok(_) => (StatusCode::OK, Json(serde_json::json!({ "ok": true }))).into_response(),
         Err(e) => e.into_response(),
     }