fix: 2-3字客户名脱敏改为 首字+* (如 徐*)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/server/auth/permissions.ts

@@ -5,7 +5,7 @@ export function maskCustomerName(name: string | null): string | null {
   if (!name) return name;
   const len = name.length;
   if (len <= 1) return '*';
-  if (len <= 3) return name[0] + '***';
+  if (len <= 3) return name[0] + '*';
   if (len <= 6) return name.slice(0, 2) + '***' + name.slice(-1);
   return name.slice(0, 4) + '***' + name.slice(-2);
 }