nodes: add cancelation, updated progress callback, typing fixes

[psychedelicious]

keeping main up to date with my api nodes branch:

• bd7e515: [nodes] Add cancelation to the API @Kyle0654
• 5fe38f7: fix(backend): simple typing fixes
  • just picking some low-hanging fruit to improve IDE hinting
• c34ac91: fix(nodes): fix cancel; fix callback for img2img, inpaint
  • makes nodes cancel immediate, use fix progress images on nodes, fix callbacks for img2img/inpaint
• 4221cf7: fix(nodes): fix schema generation for output classes
  • did this previously for some other class; needed to not have node outputs be optional

[blessedcoolant]

Approved this without testing for now. Once we are working frontend with the new backend, we can iron out any missing bugs that are bound to pop up.

[Kyle0654]

The schema_extra stuff shouldn't be necessary, and may impact how things work. Wish I'd have been able to review this 😣

[blessedcoolant]

The schema_extra stuff shouldn't be necessary, and may impact how things work. Wish I'd have been able to review this 😣

Ah crap. Sorry. I could revert or we could dish out a new PR to remove it if need be. Or merge it in as one of the changes in the nodes migration PR. I didn't want a blocker incase @psychedelicious needed to sync up with main on his PR.