Personally I tend to agree with the others about this likely being an animal doing it, and here's why: First it's food which animals are interested in while few humans would even touch scrap food from someone else. Second, humans wishing to mess with you would do something far nastier than this. Third, it's on the ground so to speak, which is as high as small animals can reach. Though I don't know how it affects birds, I do know that if you sprinkle the place and surrounding area with Cayenne Pepper 4 legged animals will stay well clear of there. Animals have very sensitive noses and the pepper is very irritating to them while on the ground it won't affect humans with their noses so far away. Just a couple bucks from the spice section at the grocery store; reapply after a week or after a rain. If the peppering ends the incidents it was an animal. If it doesn't stop it's a human (or maybe a bird) doing it.
If you are still intent on a cam:
Though I don't own one, I have researched the "Wyze" cam and believe it will be the best solution for you. You could also consider using a "Ring" brand doorbell cam which probably won't capture anything below waist level with it mounted so high, but anyone walking would be seen.
There are no cams made specifically for mounting as you'll be doing, but you can think your way around that- double-stick tape, suction cups made for other devices- something would work. You'll also need to power them somehow. Instead of a dangling wire for that, take a twist-tie from garbage or bread bag and run it into a door hinge to hold the power wire out of the way.
Another alternative would be a "Nanny Cam", which is battery powered and records only when it senses motion. My limited experience with one of these (which was disguised as a clock) showed it to be not entirely reliable, with the motion sensing range quite limited. With few recordings saved, it covered around 48 hours before the battery needed charging. It held about 30 minutes of video files in total. Other ones may be better.
You could repurpose a dashcam for this, although they're probably not the best choice. The B1W would provide very easy mounting with it being very rotatable and it just sticks in place. A 64 GB card with it will give you 6+ hours of recording. It's design is slim and discreet. Still needs a power wire.
Try the pepper first and I'll bet it stops- it's the cheapest and fastest possible solution. Betcha it solves the problem today.
Phil