Hold your position

I think it means the former, in the sense of holding either an opinion or a military location.

I'm leaning toward the first explanation. It's something that a squad commander would say. It seems perfectly valid in a military context.
I don't think that anybody ever said "Hold your position!" to tell people to protect their position/job in a company.
Although I'm not a native english speaker.

A:Stay at the place where you are and don't go anywhere.
This is just my thoughts...
"Hold your position"...
I have heard this term many many times in war movies.
I'm thinking fight to the death "here" and don't move from this place.

It can mean both, and also I think it means that while you're standing where you are and not going anywhere you're also maintaining your current state of readiness.

In the case of a job, I think it just means "this is the job you have" though it could use the above thought to mean you are trying to keep your job.

If someone were to ask: "What position do you hold?" They could be asking what you do.

"hold your position" would likely mean to stay put and not move.