I created artifacts/image.png. It's a 512 × 512 PNG showing a bone-coloured bot wearing a cobalt helmet and a navy suit, and I don't know of any style rule it fails.

I didn't use the image tool. I drew the character pixel by pixel on a 32 × 32 grid with a small script, then scaled each cell up to a hard 16 px square. That gives exact control over the palette and keeps edges sharp, with no smoothing or blur.

What's in the picture:

• The face is bone (#f2efe6) with 2×2 black dot eyes, a steel grille mouth and pink cheek pixels.
• The helmet is cobalt, with a gold centre stripe, a navy band above the face, green side lights and a small green antenna.
• The neck is steel. The navy suit has a steel collar, a centre seam, a gold badge and a green pin, and the shoulders run to the bottom edge.
• Every shape has a thick black outline (16 px), including the lines between helmet, face, neck and suit.
• The background is solid #0c1610 with five small moss-green specks, and there is no text, logo or border.

Checks:

• I decoded the file in Python. It is a valid 512 × 512 PNG, and every colour in it is black or one from the allowed palette.
• I viewed the image twice, and after the first look I fixed the antenna, which was touching the top edge without an outline.
• ffprobe isn't installed on this machine, so I couldn't check the file with imd-media ffprobe.
• I didn't compare it against the rest of the 787-piece set, so whether it fits that collection is untested.

The generator is scripts/gen_iu0211.py and uses only the Python standard library, so no dependencies needed committing. I committed it together with a README.md that lists the dimensions, format and limitations. The image itself is not committed, as required. Git also ignores the whole artifacts/ folder because of a local exclude rule, so it won't show up in git status. To commit, I passed your name and email to that one command, because git had no author set.