feature: Phase4 - Clinic two-step treatment UI

frontend/src/lib/api/treatment-catalog.ts

@@ -0,0 +1,9 @@
+import { apiClient } from './client';
+import type { TreatmentCatalogEntry } from '@/types/treatment-catalog';
+
+export const treatmentCatalogApi = {
+  list: async (): Promise<{ success: boolean; data: TreatmentCatalogEntry[] }> => {
+    const response = await apiClient.get('/treatment-catalog');
+    return response.data;
+  },
+};