fix(ssologin): missing role in SSO auto-registration and minor callback issue

[sakkyoi]

Description

Fixes an issue where users created through SSO auto-registration cannot access the system properly.

Problem

After a user is auto-registered, the role field is set to null, which prevents the user from accessing the system:

{
    "code": 200,
    "message": "success",
    "data": {
        ...
        "role": null,
        ...
    }
}

Additionally, administrators are unable to modify the affected user unless they delete the account first.

Solution

• Assign default roles to auto-registered users following the same logic as normal registration.
• Fixed a minor issue in the OIDCLoginCallback where return was missing after an error response.

[okatu-loli]

@sakkyoi Can you provide a demo video?

[sakkyoi]

Sorry for providing only screenshots, but I believe they are sufficient to demonstrate the issue.

As shown, the user is created successfully, but no role is assigned.

This behavior follows the current original logic of SSO auto-registration.

Here are my SSO settings for reference: