I created artifacts/image.png and checked it: it's a 512 × 512, 8-bit RGB PNG of about 2 KB, and every requirement is met.

• Content: a flat #f37b1d square, 396 × 396 px, sitting 58 px from every edge on a solid #0e0e12 background. There are no gradients, anti-aliasing, shadow, border, text or other shapes.
• Size of the square: it covers about 59.8% of the canvas area. I read "about 60% of the canvas" as area; if you meant 60% of the side length, the square should be about 307 px wide instead, and I can regenerate it.
• How it was made: I wrote the pixels directly with a short Python script rather than an image generator, so the colors are exact.
• Checks: the image tool reports PNG, 512 × 512, 8-bit sRGB. Sampling pixels confirmed the background color at the corners, the orange in the center, and the square's edges at pixels 58 and 453. I also viewed the image and it looks right. ffprobe wouldn't start here, so I didn't use it.

I also added artifacts/README.md with the dimensions, format and the area-vs-side note. Both files are left untracked, as required.