fix(api-docs): accept functional-component icons in EndpointSection

AntD-Vue icons (SafetyCertificateOutlined, etc.) are functional
components, so the icon prop's type: Object validator was rejecting
them with a "Expected Object, got Function" warning at runtime.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

frontend/src/pages/api-docs/EndpointSection.vue

@@ -9,7 +9,7 @@ import { safeInlineHtml } from './endpoints.js';
 
 const props = defineProps({
   section: { type: Object, required: true },
-  icon: { type: Object, default: null },
+  icon: { type: [Object, Function], default: null },
   collapsed: { type: Boolean, default: false },
 });