* Implement EnsureUserHasWorkspace Trait and Integrate into Controllers and Jobs
- Introduced the EnsureUserHasWorkspace trait to ensure users have at least one workspace when they are detached from a workspace.
- Integrated the trait into WorkspaceUserController to enforce workspace checks during user detachment.
- Updated RemoveWorkspaceGuests job to utilize the new trait for ensuring users have a workspace after detachment.
- Modified UserWorkspace model to call the ensureUserHasWorkspace method upon deletion, maintaining workspace integrity.
These changes enhance user management by ensuring that users always have a workspace, improving overall application stability.
* Add test
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Co-authored-by: Julien Nahum <julien@nahum.net>