feat(dashboard): add moderation log page + message edit history

- Backend moderation module: GET /api/moderation/stats (per-status + failed rate)
  + GET /api/moderation/actions (filter by status/actionType, cursor paging),
  joins messages for target username + content
- Message GET /api/messages/detail/:id now returns edit_count + edit_history
  (old_content snapshots from message_edits, newest first)
- FE: new /moderation page — summary cards (total/executed/failed/pending +
  failed-rate), status+type filter chips, timeline rows with action icon,
  target user, reason, status badge, timestamps, error text
- FE: message detail shows 'Riwayat edit' panel with previous versions

services/frontend/src/lib/api/index.ts

@@ -4,6 +4,7 @@ export { configApi } from "./config";
 export { dashboardApi } from "./dashboard";
 export { mediaApi } from "./media";
 export { messagesApi } from "./messages";
+export { moderationApi } from "./moderation";
 export { recordingsApi } from "./recordings";
 export { uiStateApi } from "./ui-state";
 export { voiceApi } from "./voice";

services/frontend/src/lib/api/moderation.ts

@@ -0,0 +1,23 @@
+import type { ModerationStats, PaginatedModerationActions } from "@/lib/types";
+import { api } from "./client";
+
+export const moderationApi = {
+  getStats: () => api.get<ModerationStats>("/api/moderation/stats"),
+
+  listActions: (
+    limit?: number,
+    status?: string,
+    actionType?: string,
+    cursor?: string,
+  ) => {
+    const params = new URLSearchParams();
+    if (limit) params.set("limit", String(limit));
+    if (status) params.set("status", status);
+    if (actionType) params.set("actionType", actionType);
+    if (cursor) params.set("cursor", cursor);
+    const qs = params.toString();
+    return api.get<PaginatedModerationActions>(
+      `/api/moderation/actions${qs ? `?${qs}` : ""}`,
+    );
+  },
+};