feat: 新增客服备用金台账与后台用户中文显示名

- 新增备用金账户、流水、支出、对账与权限
- 后台用户支持中文显示名并同步备用金姓名
- 审计、登录记录、任务及工单操作人优先展示中文名
- 补充备用金与人工支出方案文档

apps/backend/src/services/admin/write/task-actions.ts

@@ -96,6 +96,7 @@ export async function closeAdminTask(
         ? {
             userId: session.userId,
             username: session.username,
+            displayName: session.displayName || session.username,
             role: session.role,
           }
         : null,
@@ -140,6 +141,7 @@ export async function markAdminTaskManualReview(
         ? {
             userId: session.userId,
             username: session.username,
+            displayName: session.displayName || session.username,
             role: session.role,
           }
         : null,
@@ -215,6 +217,7 @@ export async function retryAdminTask(
         ? {
             userId: session.userId,
             username: session.username,
+            displayName: session.displayName || session.username,
             role: session.role,
           }
         : null,
@@ -335,6 +338,7 @@ export async function regenerateAdminTaskClaimLink(
         ? {
             userId: session.userId,
             username: session.username,
+            displayName: session.displayName || session.username,
             role: session.role,
           }
         : null,
@@ -394,6 +398,7 @@ export async function completeAdminTaskManualDispatch(
       ? {
           userId: Number(session.userId || 0),
           username: String(session.username || ''),
+          displayName: String(session.displayName || session.username || ''),
           role: String(session.role || ''),
         }
       : null,