Add internationalization for AI scan interval configuration

- Add aiScanInterval and scanIntervalRecommend translation keys to translations.ts
- Update TraderConfigModal to use internationalized text instead of hardcoded Chinese
- Support language switching for scan interval labels and recommendations

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

web/src/i18n/translations.ts

@@ -163,6 +163,8 @@ export const translations = {
     create: 'Create',
     configureAIModels: 'Configure AI Models',
     configureExchanges: 'Configure Exchanges',
+    aiScanInterval: 'AI Scan Decision Interval (minutes)',
+    scanIntervalRecommend: 'Recommended: 3-10 minutes',
     useTestnet: 'Use Testnet',
     enabled: 'Enabled',
     save: 'Save',
@@ -575,6 +577,8 @@ export const translations = {
     create: '创建',
     configureAIModels: '配置AI模型',
     configureExchanges: '配置交易所',
+    aiScanInterval: 'AI 扫描决策间隔 (分钟)',
+    scanIntervalRecommend: '建议: 3-10分钟',
     useTestnet: '使用测试网',
     enabled: '启用',
     save: '保存',