feat(user): wear badge modal and user-center entry

Expose 我的徽章 modal on profile header with REST wear actions and
update SPA badge help for icon_url + grant/wear flows.

assets/css/routes/user-center/credits.css

@@ -986,3 +986,10 @@ body.uc-modal-open {
   color: var(--focus-color, #f04494);
 }
 .focus-color { color: var(--focus-color, #f59e0b); }
+
+/* User badges wear modal */
+.uc-badges-list { max-height: 60vh; overflow: auto; }
+.uc-badges-item { gap: 12px; }
+.uc-badges-item .medal-icon { width: 28px; height: 28px; object-fit: contain; }
+.uc-badges-wear-tag { margin-left: 6px; }
+.uc-badges-empty { padding: 16px 0; text-align: center; }