Exception in thread "main" org.hibernate.AnnotationException: - Use of @OneToMany or @ManyToMany targeting an unmapped class:

The problem is in this block:

    @Column(name = "addresses")
    @OneToMany(mappedBy = "client", cascade = CascadeType.ALL, fetch = FetchType.EAGER)
    private List<AddressDataSet> addresses = new ArrayList<>();

You either use @Column or a@One/ManyToOne/Many relation. You cannot use both. The first one is for mapping primitive data types. The other one is for entities relations. Remove @Column and you should be good to go.

Update

You added Client as annotated class, but not AddressDataSet. Add it just under the addAnnotatedClass(Client.class):

var metadata = new MetadataSources(serviceRegistry)
                .addAnnotatedClass(Client.class)
                .addAnnotatedClass(AddressDataSet.class)
                .getMetadataBuilder()
                .build();