Add username support for Ubisoft games

[kaifcodec]

Ubisoft Username Availability Checker

Ubisoft doesn’t expose a clear public API for checking username availability, so this feature will require some investigation.

Suggested approach for contributors:

• Observe the Ubisoft account creation flow.
• Capture network traffic during the signup process to identify any internal endpoint used for validating usernames.
• Once found, implement the username checker following the project’s existing structure.
• Add proper error handling and fallbacks in case Ubisoft modifies or restricts the endpoint.

This issue is suitable for contributors who enjoy a bit of reverse-engineering and exploratory work.
Once found:

• Put the module in gaming category.