I'm not sure what exactly it means, because it means nothing at all.

Means they did not reject you from the start, but that doesn't mean you're out of the woods just yet. They are being careful with their words cause discriminating against you for your DACA status is hugely illegal.

HR is not your friend, at best they are co-workers, but in reality you should be ultra careful around them. HR exists only to protect the company, from you.

Just because its illegal to discriminate against you for your DACA status, doesn't mean they wont try and do it. They will find some weasel way to do it. Like saying youre a bad fit for the job. Or your qualifications are lacking, lack of cultural fit, not enough experience when you actually do have it, or some other weaselly way.