Warn user about recursive project deletion when deleting a parent project

[lukas-braune]

Current Behavior

When a user deletes a parent project in DT, all child projects are also deleted without explicit warning or confirmation. This may lead to unintended data loss if the user is not aware of the recursive deletion behavior.

Proposed Behavior

When a user attempts to delete a parent project in DT, a warning message should be displayed indicating that all child projects will also be deleted. This warning should prompt the user to confirm the deletion.

Checklist

• I have read and understand the contributing guidelines
• I have checked the existing issues for whether this enhancement was already requested