[New Extension] Corridor Crawler Outpainting

[brick2face]

https://github.com/brick2face/corridor-crawler-outpainting

@ClashSAN

An extension for generating hallways with the depth-to-image model at 512 resolution. It can be tweaked to work with other models/resolutions. Eventually I'd like to add support for animations and some quality-of-life features, but currently I think what it does is pretty neat.