Add internal information for processing tasks

[acorderob]

I'm an extension developer, and i would want my extension to act differently for each processing task in a generation based on what kind of processing it is.

For example: a txt2img using adetailer would have the first regular t2i process and then multiple adetailer i2i processes depending on the adetailer configured models and their detections. I would want my extension to differentiate when the process is from adetailer, and what model it is. This would of course need support from adetailer, but a1111 would need to first lay the foundation for this information to be available in the processing object, maybe as some optional fields to indicate which addon added the process and another for addon-specific details (like the model in this case).

Thoughts?