🐛 fix(shortcuts): 调整新建查询默认快捷键

- 将新建查询页默认快捷键改为 macOS Cmd+N、Windows Ctrl+N
- 将新建数据源默认快捷键顺延为 Cmd/Ctrl+Shift+N
- 补充默认快捷键唯一性校验，避免动作默认撞键

frontend/src/utils/shortcuts.test.ts

@@ -178,14 +178,27 @@ describe('shortcut defaults', () => {
     });
   });
 
+  it('keeps enabled default shortcuts unique per platform', () => {
+    for (const platform of ['mac', 'windows'] as const) {
+      const seen = new Map<string, string>();
+      Object.entries(DEFAULT_SHORTCUT_OPTIONS).forEach(([action, bindings]) => {
+        const binding = bindings[platform];
+        if (!binding.enabled || !binding.combo) return;
+        const existingAction = seen.get(binding.combo);
+        expect(existingAction, `${platform} ${binding.combo} is shared by ${existingAction} and ${action}`).toBeUndefined();
+        seen.set(binding.combo, action);
+      });
+    }
+  });
+
   it('uses Navicat-inspired defaults separately for macOS and Windows/Linux', () => {
     expect(DEFAULT_SHORTCUT_OPTIONS.runQuery).toEqual({
       mac: { combo: 'Meta+R', enabled: true },
       windows: { combo: 'Ctrl+R', enabled: true },
     });
     expect(DEFAULT_SHORTCUT_OPTIONS.newQueryTab).toEqual({
-      mac: { combo: 'Meta+Y', enabled: true },
-      windows: { combo: 'Ctrl+Q', enabled: true },
+      mac: { combo: 'Meta+N', enabled: true },
+      windows: { combo: 'Ctrl+N', enabled: true },
     });
     expect(DEFAULT_SHORTCUT_OPTIONS.toggleLogPanel).toEqual({
       mac: { combo: 'Meta+Shift+H', enabled: true },
@@ -195,8 +208,8 @@ describe('shortcut defaults', () => {
 
   it('registers connection and AI panel actions as real shortcuts', () => {
     expect(DEFAULT_SHORTCUT_OPTIONS.newConnection).toEqual({
-      mac: { combo: 'Meta+N', enabled: true },
-      windows: { combo: 'Ctrl+N', enabled: true },
+      mac: { combo: 'Meta+Shift+N', enabled: true },
+      windows: { combo: 'Ctrl+Shift+N', enabled: true },
     });
     expect(DEFAULT_SHORTCUT_OPTIONS.toggleAIPanel).toEqual({
       mac: { combo: 'Meta+J', enabled: true },
@@ -215,21 +228,21 @@ describe('shortcut defaults', () => {
       mac: { combo: 'Ctrl+Shift+R', enabled: false },
       windows: { combo: 'Ctrl+Shift+R', enabled: false },
     });
-    expect(options.newQueryTab.windows.combo).toBe('Ctrl+Q');
+    expect(options.newQueryTab.windows.combo).toBe('Ctrl+N');
   });
 
   it('sanitizes partial platform shortcut bindings without losing defaults', () => {
     const options = sanitizeShortcutOptions({
       newQueryTab: {
-        mac: { combo: 'Meta+Y', enabled: false },
+        mac: { combo: 'Meta+N', enabled: false },
       },
       sendAIChatMessage: {
         windows: { combo: 'A', enabled: true },
       },
     });
 
-    expect(options.newQueryTab.mac).toEqual({ combo: 'Meta+Y', enabled: false });
-    expect(options.newQueryTab.windows).toEqual({ combo: 'Ctrl+Q', enabled: true });
+    expect(options.newQueryTab.mac).toEqual({ combo: 'Meta+N', enabled: false });
+    expect(options.newQueryTab.windows).toEqual({ combo: 'Ctrl+N', enabled: true });
     expect(options.saveQuery.windows).toEqual({ combo: 'Ctrl+S', enabled: true });
     expect(options.sendAIChatMessage.windows).toEqual({ combo: 'Enter', enabled: true });
   });
@@ -237,13 +250,13 @@ describe('shortcut defaults', () => {
   it('resolves and displays platform-specific bindings', () => {
     const options = sanitizeShortcutOptions({
       newQueryTab: {
-        mac: { combo: 'Meta+Y', enabled: true },
-        windows: { combo: 'Ctrl+Q', enabled: true },
+        mac: { combo: 'Meta+N', enabled: true },
+        windows: { combo: 'Ctrl+N', enabled: true },
       },
     });
 
     expect(resolveShortcutBinding(options, 'newQueryTab', 'mac')).toEqual({
-      combo: 'Meta+Y',
+      combo: 'Meta+N',
       enabled: true,
     });
     expect(getShortcutDisplayLabel('Meta+N', 'mac')).toBe('⌘N');
@@ -257,7 +270,7 @@ describe('shortcut defaults', () => {
     expect(getPrimaryShortcutDisplayLabel('C', 'windows')).toBe('Ctrl+C');
     expect(getPrimaryShortcutDisplayLabel('Enter', 'mac')).toBe('⌘↵');
     expect(getPrimaryShortcutDisplayLabel('Enter', 'windows')).toBe('Ctrl+Enter');
-    expect(resolveShortcutDisplay(options, 'newQueryTab', 'windows')).toBe('Ctrl+Q');
+    expect(resolveShortcutDisplay(options, 'newQueryTab', 'windows')).toBe('Ctrl+N');
   });
 });
 

frontend/src/utils/shortcuts.ts

@@ -191,13 +191,13 @@ export const DEFAULT_SHORTCUT_OPTIONS: ShortcutOptions = {
     windows: { combo: 'Ctrl+K', enabled: true },
   },
   newQueryTab: {
-    mac: { combo: 'Meta+Y', enabled: true },
-    windows: { combo: 'Ctrl+Q', enabled: true },
-  },
-  newConnection: {
     mac: { combo: 'Meta+N', enabled: true },
     windows: { combo: 'Ctrl+N', enabled: true },
   },
+  newConnection: {
+    mac: { combo: 'Meta+Shift+N', enabled: true },
+    windows: { combo: 'Ctrl+Shift+N', enabled: true },
+  },
   toggleAIPanel: {
     mac: { combo: 'Meta+J', enabled: true },
     windows: { combo: 'Ctrl+J', enabled: true },