dashboard: return problem details directly from client-error handlers

hive-c0re/src/dashboard/questions.rs

@@ -28,7 +28,8 @@ pub(super) struct AnswerForm {
 /// cross-origin form-POST couldn't already reach. This shim disappears
 /// once the unifying gateway makes the agent page same-origin; see
 /// `docs/boundary.md`.
-fn with_cors(mut resp: Response) -> Response {
+fn with_cors(resp: impl IntoResponse) -> Response {
+    let mut resp = resp.into_response();
     resp.headers_mut().insert(
         axum::http::header::ACCESS_CONTROL_ALLOW_ORIGIN,
         axum::http::HeaderValue::from_static("*"),
@@ -45,8 +46,7 @@ pub(super) async fn post_answer_question(
     if answer.is_empty() {
         return with_cors(
             ProblemDetails::from_status_code(StatusCode::BAD_REQUEST)
-                .with_detail("answer: required")
-                .into_response(),
+                .with_detail("answer: required"),
         );
     }
     let resp = match state