Great job on this, I played this to the end and had fun playing it! The cool animations (e.g. the robot explosions, shooting, robot electroshock, portal, etc.) made the gameplay more fun, the music was great, and the platforming design was great, too. And it seems like a small thing, but the way the player takes damage also felt nicely polished and fair. I would have been happy to play more!
Some hopefully helpful player feedback: when my character was standing on the ground and against a wall, the jump button didn't work. So once I was close to a wall that I wanted to jump over or up, I had to first move away from the wall, and then jump back towards it. Maybe something in the wallslide code is blocking the normal functioning of the jump? The other feedback I'd have is that if you make the fire button shoot the flame more quickly (shortening the time between when I press the button and when the flame comes out, as opposed to the speed of the flame), it would feel nicer and more responsive. There was a point where I wanted to jump and shoot a robot at the apex of my jump, and I ended up pushing jump and shoot at almost the same time to get the timing to work. I know you probably want the raising-gun-and-aiming animation to fully run before the flame comes out, but maybe fewer frames or a faster animation would improve this?
Again, great work!