There are a few latches that have that as a built-in option, but they tend to be very expensive. What country are you in? The device selection does vary.
More commonly, depending on the specifics of the latch design, you can probably go a DIY route just with a contact sensor. These come in different sizes and shapes and it’s just going to let you know when the bolt is pushed all the way in. Several community members have done these for dumb deadbolts, for example.
Can you post a picture of the window latch so we can see the exact mechanism?
Meanwhile, in the following post, you can see how one community member made one for a manual deadbolt. The post is from almost 10 years ago, so you would probably be using different specific device models now, but the approach would be the same.