035-workspaces-personal: requires AD directory user for non-interactive testing

## Problem
The WorkSpaces tutorial requires a user to exist in the Active Directory before creating a WorkSpace. Simple AD user creation needs LDAP tools or a domain-joined EC2 instance.

## Current state
- Simple AD directory deployed via `000-prereqs-directory` CFN stack
- Directory registered with WorkSpaces
- Script finds the directory but fails because the auto-generated username doesn't exist in AD

## Steps to resolve
1. Launch a domain-joined EC2 instance in the directory's VPC
2. Use AD tools to create a test user
3. Or: modify the script to use the WorkSpaces API to create a user (if supported)
4. Test the script end-to-end
5. Add back to the non-interactive PR

从 035-workspaces-personal 的脚本和 000-prereqs-directory CloudFormation 堆栈开始，确认如何找到目录以及生成的用户名在哪里使用。检查 WorkSpaces API 是否支持创建用户；如果不支持，则使用加入域的 EC2 实例和 AD 工具。完成的标准是脚本能够端到端运行，并恢复到非交互式 PR。

由索引模型根据 Issue 内容生成。