fix: avoid double free and fix sdxl lora naming conversion
* Fixed a double free issue when running multiple backends on the CPU, eg: CLIP
and the primary backend, as this would result in the *_backend pointers both
pointing to the same thing resulting in a segfault when calling the
StableDiffusionGGML destructor.
* Improve logging to allow for a color switch on the command line interface.
Changed the base log_printf function to not bake the log level directly into
the log buffer as that information is already passed the logging function via
the level parameter and it's easier to add in there than strip it out.
* Added a fix for certain SDXL LoRAs that don't seem to follow the expected
naming convention, converts over the tensor name during the LoRA model
loading. Added some logging of useful LoRA loading information. Had to
increase the base size of the GGML graph as the existing size results in an
insufficient graph memory error when using SDXL LoRAs.
* small fixes
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Co-authored-by: leejet <[email protected]>
