Changed logic and optimized ObjectID in ObjectDB and Variant, removed…

Refactored how ObjectID works in ObjectDB, it is now very fast to obtain an object pointer from an ObjectID. Also, RefPtr was removed and the referencing logic for Refecence has been replicated inside Variant. This hugely simplifies the code and logic.

Finally, the functions to check if an object pointer is invalid were removed given they are dangerous and unfixable. Instead, Variant now contains an ObjectID together with the pointer, which ensures validity can be checked at all times.

Also fixes #32383