Add --root option to user management CLI utilities

[Copilot]

Summary

invoke-useradd, invoke-userdel, invoke-usermod, and invoke-userlist had no way to specify the InvokeAI root directory from the command line, making them difficult to use in multi-root deployments.

• Adds --root / -r argument to all four entry points in invokeai/app/util/user_management.py
• When --root is provided, sets os.environ["INVOKEAI_ROOT"] before get_config() is first called (it's @lru_cache-backed), so InvokeAIAppConfig.find_root() picks up the override
• INVOKEAI_ROOT env var was already respected via find_root() — no change needed there

invoke-userlist --root /path/to/invokeai
invoke-useradd --root /path/to/invokeai --email user@example.com --password secret

Related Issues / Discussions

Closes #[issue]

QA Instructions

Run any user management command with --root /some/invokeai/path and verify it reads/writes users from the database at that root. Also verify INVOKEAI_ROOT=/some/path invoke-userlist continues to work without --root.

Merge Plan

N/A

Checklist

• The PR has a short but descriptive title, suitable for a changelog
• Tests added / updated (if applicable)
• ❗Changes to a redux slice have a corresponding migration
• Documentation added / updated (if applicable)
• Updated What's New copy (if doing a release after this PR)

Original prompt

---

This section details on the original issue you should resolve

<issue_title>[bug]: User management utilities should accept a —root option.</issue_title>
<issue_description>### Is there an existing issue for this problem?

• I have searched the existing issues

Install method

Invoke's Launcher

Operating system

Linux

GPU vendor

Nvidia (CUDA)

GPU model

No response

GPU VRAM

No response

Version number

feature/multiuser

Browser

No response

System Information

No response

What happened

The user management commands invoke-useradd, invoke-userdel, invoke-usermod and invoke-userlist should accept a —root argument to select the invokeai root directory. They should also respect the INVOKEAI_ROOT environment variable, which does the same thing.

What you expected to happen

These commands should accept —root and respect INVOKEAI_ROOT.

How to reproduce the problem

No response

Additional context

No response

Discord username

No response</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes [bug]: User management utilities should accept a —root option. #80

---

💡 You can make Copilot smarter by setting up custom instructions, customizing its development environment and configuring Model Context Protocol (MCP) servers. Learn more Copilot coding agent tips in the docs.

[lstein]

works as advertised