Resource model 'user' field is Optional[User] but it is required.

[marrobi]

All resources get a value for user, however this is done on save, rather than creation of the object. We should refactor so that the user property gets set on creation of the object, and remove the Optional form here.

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The 'user' field is Optional[User], but there is no null check before accessing its attributes. This could lead to an AttributeError if 'user' is None. Add a null check before accessing 'user' attributes.

Originally posted by @Copilot in #3770 (comment)