Feedback categories page; treat 204 responses as success

Feedback → Categories: add, rename, reorder, archive/restore, and delete
unused categories. Feedback rows show the category's current label.

The API helper now accepts 204 No Content, which previously surfaced as a
"No Content" error after archive/delete and quiz attempt resets.

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

lib/api.ts

@@ -36,6 +36,9 @@ async function call<T>(
     headers: { "Content-Type": "application/json", ...(init?.headers ?? {}) },
     ...init,
   });
+  // 204 No Content (archive, delete, reset…) is success with no body —
+  // there's no JSON to parse.
+  if (res.status === 204) return { data: undefined as T };
   let body: Envelope<T>;
   try {
     body = (await res.json()) as Envelope<T>;
@@ -191,6 +194,8 @@ export type AdminCollection = {
 export type AdminFeedback = {
   id: string;
   category: string;
+  /** The category's current display name. */
+  category_label?: string;
   message: string;
   contact_email: string | null;
   created_at: string;
@@ -748,3 +753,40 @@ export const quizzes = {
   resetParticipant: (id: string, userId: string) =>
     call<void>(`/admin/quizzes/${id}/participants/${userId}`, { method: "DELETE" }),
 };
+
+// ─── Feedback categories ────────────────────────────────────────────────────
+
+/** One option on the app's /feedback form. `key` is fixed once created. */
+export type FeedbackCategory = {
+  key: string;
+  label: string;
+  description: string;
+  sort_order: number;
+  archived_at?: string | null;
+  /** How much feedback is filed under it. */
+  usage_count?: number;
+};
+
+export const feedbackCategories = {
+  list: () =>
+    call<FeedbackCategory[]>("/admin/feedback/categories").then((r) => r.data),
+  create: (label: string, description: string) =>
+    call<FeedbackCategory>("/admin/feedback/categories", {
+      method: "POST",
+      body: JSON.stringify({ label, description }),
+    }).then((r) => r.data),
+  update: (key: string, v: { label: string; description: string; archived: boolean }) =>
+    call<void>(`/admin/feedback/categories/${encodeURIComponent(key)}`, {
+      method: "PUT",
+      body: JSON.stringify(v),
+    }),
+  remove: (key: string) =>
+    call<void>(`/admin/feedback/categories/${encodeURIComponent(key)}`, {
+      method: "DELETE",
+    }),
+  reorder: (keys: string[]) =>
+    call<void>("/admin/feedback/categories/order", {
+      method: "PUT",
+      body: JSON.stringify({ keys }),
+    }),
+};