fix(language-service): use default html data provider for document symbols (#5968)

Co-authored-by: KazariEX <zinkawaii@qq.com>

Author: liangmiQwQ

packages/language-service/lib/plugins/vue-template.ts

@@ -596,6 +596,22 @@ export function create(
 						}
 					}
 				},
+
+				provideDocumentSymbols(document, token) {
+					if (document.languageId !== languageId) {
+						return;
+					}
+					const info = resolveEmbeddedCode(context, document.uri);
+					if (info?.code.id !== 'template') {
+						return;
+					}
+
+					updateExtraCustomData([
+						html.getDefaultHTMLDataProvider(),
+					]);
+
+					return baseServiceInstance.provideDocumentSymbols?.(document, token);
+				},
 			};
 
 			async function runWithVueDataProvider<T>(