vtracer only decodes input, but image's default features pulled a full AV1
encoder (ravif/rav1e) and OpenEXR into the CLI binary and the Python wheel.
Restrict to decode-only input formats (png, jpeg, gif, bmp, webp, tiff, ico,
pnm, tga, qoi). The release binary drops from ~3.23 MB to ~2.46 MB and builds
faster; supported inputs are unchanged in practice (avif decode was never in
image's defaults anyway).
`vtracer in.png out.svg` now works alongside the `-i/--input` and
`-o/--output` flags. Input/output become optional positionals plus the
existing flags; an explicit flag wins over the positional, and a clear error
is shown if neither is given.
Chris Tsang