✨ feat(query-editor): 支持自定义新建查询默认 SQL

- 在 appearance 持久化设置中新增 newQuerySqlTemplate，支持默认回退与空白模板
- 新建空白查询标签页按用户模板初始化，不影响外部 SQL、保存查询和只读标签
- 在工具中心补充模板编辑与恢复默认入口，并完善 store、编辑器和 i18n 回归测试

frontend/src/components/QueryEditor.external-sql-save.test.tsx

@@ -49,7 +49,10 @@ const storeState = vi.hoisted(() => ({
   saveQuery: vi.fn(),
   theme: 'light',
   languagePreference: 'zh-CN' as 'zh-CN' | 'en-US',
-  appearance: { uiVersion: 'legacy' as 'legacy' | 'v2' },
+  appearance: {
+    uiVersion: 'legacy' as 'legacy' | 'v2',
+    newQuerySqlTemplate: null as string | null,
+  },
   sqlFormatOptions: { keywordCase: 'upper' as const },
   setSqlFormatOptions: vi.fn(),
   queryOptions: {
@@ -705,6 +708,7 @@ describe('QueryEditor external SQL save', () => {
     storeState.aiPanelVisible = false;
     storeState.setAIPanelVisible.mockReset();
     storeState.appearance.uiVersion = 'legacy';
+    storeState.appearance.newQuerySqlTemplate = null;
     storeState.queryOptions = {
       maxRows: 5000,
       showColumnComment: true,
@@ -833,6 +837,26 @@ describe('QueryEditor external SQL save', () => {
     expect(editorState.value).toBe('SELECT * FROM ');
   });
 
+  it('uses the customized new query template for a fresh blank query tab', async () => {
+    storeState.appearance.newQuerySqlTemplate = 'SELECT id,\n       name\nFROM users;';
+
+    await act(async () => {
+      create(<QueryEditor tab={createTab({ query: '' })} />);
+    });
+
+    expect(editorState.value).toBe('SELECT id,\n       name\nFROM users;');
+  });
+
+  it('allows a blank new query template when the default content is cleared', async () => {
+    storeState.appearance.newQuerySqlTemplate = '';
+
+    await act(async () => {
+      create(<QueryEditor tab={createTab({ query: '' })} />);
+    });
+
+    expect(editorState.value).toBe('');
+  });
+
   it('keeps the query results panel hidden by default on first entry', async () => {
     storeState.appearance.uiVersion = 'v2';
 

frontend/src/components/QueryEditor.tsx

@@ -124,6 +124,7 @@ import {
     queryCompletionMetadataRowsBySpecs,
     readSidebarSqlDropText,
     matchLeadingSelectTableReference,
+    resolveNewQueryDefaultTemplate,
     resolveEventTargetNode,
     resolveNextResultSetIndex,
     resolveOracleExactCaseTableReference,
@@ -759,7 +760,11 @@ const resetSharedQueryEditorMetadata = () => {
 
 
 const QueryEditor: React.FC<{ tab: TabData; isActive?: boolean }> = ({ tab, isActive = true }) => {
-  const [query, setQuery] = useState(getInitialEditorQuery(tab));
+  const appearance = useStore(state => state.appearance);
+  const [query, setQuery] = useState(() => getInitialEditorQuery(
+      tab,
+      resolveNewQueryDefaultTemplate(appearance.newQuerySqlTemplate),
+  ));
   const isExternalSQLFileTab = Boolean(String(tab.filePath || '').trim());
   const isObjectEditQueryTab = tab.type === 'query' && tab.queryMode === 'object-edit';
   
@@ -860,7 +865,6 @@ const QueryEditor: React.FC<{ tab: TabData; isActive?: boolean }> = ({ tab, isAc
   const theme = useStore(state => state.theme);
   const languagePreference = useStore((state) => state.languagePreference);
   void languagePreference;
-  const appearance = useStore(state => state.appearance);
   const darkMode = theme === 'dark';
   const isV2Ui = appearance.uiVersion === 'v2';
   const sqlFormatOptions = useStore(state => state.sqlFormatOptions);

frontend/src/components/queryEditor/QueryEditorHelpers.ts

@@ -682,11 +682,25 @@ export const splitCompletionSchemaAndTable = (qualified: string): { schema: stri
 
 export const DEFAULT_QUERY_TEMPLATE = 'SELECT * FROM ';
 
+export const resolveNewQueryDefaultTemplate = (
+    template: string | null | undefined,
+): string => {
+    if (template === null || template === undefined) {
+        return DEFAULT_QUERY_TEMPLATE;
+    }
+    return String(template)
+        .replace(/\r\n/g, '\n')
+        .replace(/\r/g, '\n');
+};
+
 export const getTabQueryValue = (tab: TabData): string => (
     typeof tab.query === 'string' ? tab.query : ''
 );
 
-export const getInitialEditorQuery = (tab: TabData): string => {
+export const getInitialEditorQuery = (
+    tab: TabData,
+    defaultQueryTemplate: string | null | undefined = DEFAULT_QUERY_TEMPLATE,
+): string => {
     if (hasQueryTabDraft(tab.id)) {
         return getQueryTabDraft(tab.id);
     }
@@ -694,7 +708,7 @@ export const getInitialEditorQuery = (tab: TabData): string => {
     if (tabQuery || tab.filePath || tab.savedQueryId || tab.readOnly) {
         return tabQuery;
     }
-    return DEFAULT_QUERY_TEMPLATE;
+    return resolveNewQueryDefaultTemplate(defaultQueryTemplate);
 };
 
 export const resolveNextResultSetIndex = (sets: Array<{ key?: string }>): number => {