Can the person getting the restraining order cause a violation by deliberately coming within the proscribed distance

Yes, of course, and then the person who has the restraining order against him/her uses that as a defense.

You ask about an inadvertent act as well as a deliberate act.

Which is it?

Yes, it can not be deliberate and inadvertent both??

If you are in Walmart shopping, and they come into the store, not knowing you are there, they turn the corner of the isle and poof, you are standing there.

The how, when and where will all make a difference

Deliberate

And did they try to get them arrested over it ?

It is a what if. What would a person do if they came home from work and the person was setting on the front porch?

Which party are you in all of this?

If the person on the porch is the one under restraint then you call the police. Also you press stalking charges.

If the person on the porch is the holder of the restraining order and it is your house. Call the police and report them for tresspass. Let them handle it and remove the person. Do Not approach them.

Let me see - there's a no contact/restraining order, the person who got the order sits on the other person's front porch, what should the first person do?

Call the Police.