Motivation
sometimes when upscaling images in a batch, or resizing them, etc. its possible to crash the entire computer because i unwittingly ran an operation that would result in a 8192+ pixels wide/tall image, and processing it takes up 100% of both the cpu and gpu memory. somewhat related to #2671

Description
when an operation will result in an image being more than 4k resolution at any point, pop up a confirmation window saying something like, "Warning: the current configuration will likely freeze your entire computer due to massive image sizes. do you wish to continue?"

Alternatives
nodes could visibly turn bright orange with caution stripes or something if they detect an overly large image, and hovering over them will show tooltip-esque text explaining the potential memory overuse. heres a very rough mockup:

another alternative, which deals with the root of the issue, would be to have a setting that hard-limits how much memory chainner is allowed to use at any given time- so i could set it to half my installed system memory, or half of my gpu memory, for example.
the following screenshot is from a minecraft launcher, and controls java memory limits, but communicates the same concept: