Confusing error when running migrations with issues

Nobody has claimed this yet.

If you have the following

```crystal
def migrate
create table_for(Comment) do
primary_key id : UUID
add_timestamps
add_belongs_to user : User, on_delete: :cascade
end
end
```

Then you run `lucky db.migrate`, you may run in to an error that mentions something like:
```
foreign key constraint "comment_user_id_fkey" cannot be implemented (Exception)
```

This is because the user id might be `UUID`, but you forgot to add the `foreign_key_type: UUID` to your `add_belongs_to`.

If we have a way to catch this error, we should.

Start at the migration path invoked by `lucky db.migrate` and inspect how `add_belongs_to` handles a UUID foreign key when `foreign_key_type` is omitted. Reproduce the example with `Comment` and `User`; done means the migration reports a clear, actionable error instead of the raw foreign-key constraint failure.

Written by the indexing model from the issue text.