Reference Concat's contact-sheet mode picked cell size from the median
of the batch, so a single low-res reference capped every other tile's
resolution once upstream batching forced a common size.
Add Image List: auto-expanding IMAGE sockets (same pattern as Dynamic
LoRA Stack) that output a native ComfyUI list instead of a stacked
tensor, so mixed-resolution references never get resized before
Reference Concat sees them.
Reference Concat now declares INPUT_IS_LIST, accepts either an Image
List or a legacy stacked batch, sizes its contact sheet from the
largest reference (upscaling smaller ones to match instead of the
reverse), and adds an interpolation widget (nearest/bilinear/bicubic/
lanczos) used for all internal resizing.
