It's not correct grammatically to say Someone has stolen my car last night.
We use the past simple tense instead of the present perfect tense when talking about such occurences happening in the (very) recent past.
And equivalently, you must say, in the passive voice this: My car was stolen( not has been stolen) last night.
She bought a little cup—
which had been filled with butter : this means someone, perhaps a lavish shopkeeper, had filled the cup with butter. Here the doer of the action is made more prominent than the action itself.
has been filled with butter.: this means someone filled the cup with butter after she had bought it. In other words, it wasn't already filled with butter.
was filled with butter.: this conveys the same idea as 1,only that here there is no emphasis on the doer of the action (butter-filling). It's the action itself that is made more prominent here.