feat: Move notification settings to user profile and add i18n support

- Move notification config from system settings (.env) to user profile (database)
- Add user-specific notification settings API endpoints (GET/PUT /api/user/notification-settings)
- Add notification_settings column to qd_users table
- Update portfolio and trading-assistant to use profile notification settings
- Add notification settings UI in profile page with all channels (browser, telegram, email, phone, discord, webhook)
- Add i18n translations for notification settings in 10 languages
- Fix timestamp parsing in TradingRecords and portfolio (handle both ISO strings and Unix timestamps)
- Fix header icons alignment for mobile responsive layout
- Fix equity curve timestamp bug (handle datetime objects properly)
- Remove unused login.js exports and clean up user.js store
- Remove husky, commitlint and other dev dependencies
- Clean up env.example by removing user-specific notification params
- Update signal_notifier to prioritize user-specific tokens over global env vars

quantdinger_vue/src/api/user.js

@@ -125,6 +125,28 @@ export function changePassword (data) {
   })
 }
 
+/**
+ * Get current user's notification settings
+ */
+export function getNotificationSettings () {
+  return request({
+    url: '/api/users/notification-settings',
+    method: 'get'
+  })
+}
+
+/**
+ * Update current user's notification settings
+ * @param {Object} data - { default_channels, telegram_chat_id, email, discord_webhook, webhook_url, phone }
+ */
+export function updateNotificationSettings (data) {
+  return request({
+    url: '/api/users/notification-settings',
+    method: 'put',
+    data
+  })
+}
+
 /**
  * Get current user's credits log
  * @param {Object} params - { page, page_size }