This question was said in a movie. A man asking a woman "how long have you lived here?" and they were having dinner. I thought that he had to say "How long have you been living here?".
As a learner, I can say, based on my grammar book, that:
When we talk about situation that exists until the present, we can often use either the present perfect or present perfect continuous:
We've been looking forward to this holiday for months.
We've looked forward to this holiday for months.
It is worth to mention that, there are two main situations in which we use present perfect continuous rather present perfect:
We use present perfect continuous for suggesting repeated activity:
He has been kicking a football all day. (but, he has played in 54 national matches)
We use present perfect continuous for focusing on the process:
prices have been decreasing recently (but, prices have decreased by 4%)