`PC_PATH_MAX` doesn't exist for (some?) external drives on macOS. We need error handling when retrieving this value.
Also added error handling for `PC_NAME_MAX` just in case. This does work for me for external drives on macOS, though.
Closes#6277
There are only a couple SDXL inpainting models, and my tests indicate they are not as good as SD1.5 inpainting, but at least we support them now.
- Add the config file. This matches what is used in A1111. The only difference from the non-inpainting SDXL config is the number of in-channels.
- Update the legacy config maps to use this config file.
- Use the our adaptation of the HWC3 function with better types
- Extraction some of the util functions, name them better, add comments
- Improve type annotations
- Remove unreachable codepaths
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