feat(api, agents, i18n): enhance settlement features and multi-language support

Added new types and API functions for settlement period summaries and credit ledgers, improving the management of agent settlements. Updated the admin console to reflect these changes, enhancing user experience with better navigation and data presentation. Additionally, expanded multi-language support by incorporating new translations in English, Nepali, and Chinese for settlement-related terms, ensuring consistency across the platform.

src/i18n/locales/zh/agents.json

@@ -164,7 +164,7 @@
     "periodPlaceholder": "选择账期",
     "allPeriods": "全部账期",
     "filteredByPeriodRange": "账期 {{range}} 的账单",
-    "emptyNoPeriodsManage": "尚无账期与账单。请在下方「账期管理」点「本周」开期，到期后关账，账单会自动出现在这里。",
+    "emptyNoPeriodsManage": "尚无账单。请在结算中心完成「关账出账」后，账单会出现在此处。",
     "emptyNoPeriodsAgent": "尚无账单。账期由上级或平台关账后自动生成，无需您手动筛选时间。",
     "emptyNoClosed": "当前没有已关账的账期，账单尚未生成。请等待负责人关账后再查看。",
     "typePlayer": "玩家账单",
@@ -273,7 +273,7 @@
     "range": "账期",
     "statusOpen": "进行中",
     "statusClosed": "已关账",
-    "empty": "尚无账期。点「本周」等快捷账期后开期，到期后在此关账。",
+    "empty": "尚无账期，请选择快捷账期开期。",
     "start": "开始",
     "end": "结束",
     "status": "状态",