Put the legs back on your stove. That's not cool to do because you're re-engineering the stove. You have a flammable floor underneath the stove it needs to be adjusted to the right height for air to flow. I have the same problem at my house after doing a remodel. After looking around I found this to be the simplest solution. I went to internet and found a company that sells rubber. I bought a 10 ft long by 1 inch by a half inch thick. I measured the distance from the back of the stove to the front of the stove to get the correct cut. I had to make a few passes to get through the rubber but it worked and I was pleased with the outcome. I'm going to glue a piece of plastic to the front edge that I cut which is exposed to make it appears though it is a finished product.

This is correct - a slide-in will fit as is (though I will need to fix that strip at the back). In my case the gap is very uneven so really want to fill in the sides for aesthetics. I did find this one site that makes filler trim (link below) but looks like a custom order. Seems like a common problem so baffled why a simple trim filler isn't easy to find. Here is a link that might be useful: Microtrim

Years ago, slide in ranges typically required a strip at the back. Today, most are sized to fit a full-depth cutout. I think you'll be fine if you have the strip removed. I'd recommend continuing your backsplash tile one row below the counter level, and then butt the range up to that. The over door will still project from the cabinet fronts, as it should.

For fire safety reasons the range must be installed with the sides no further back than flush with the front of your cabinet door and drawer, ie the oven door gasket and door project beyond the face of cabinet doors. It appears your back granite spacer could be a little smaller but also the photo doesn't make clear if your control panel would be hitting your countertop front edge before being pushed the maximum safe distance, thus entailing notching the granite to fit. Just a FYI if you use self clean cycle good idea to pull open adjacent door and drawers to prevent scorching of your vinyl wrap doors-friends had to replace their adjacent doors for that reason. A judgement call if your granite guy would do adjustment for free or for what charge. Once you are back to using your new kitchen you may or may not regularly notice the small amount of projection, the focus will be on your new granite.