Krea 2 LoRA DreamBooth trainer (#14046)
* Add Krea 2 LoRA DreamBooth trainer + Krea2 LoRA loader
Adds examples/dreambooth/train_dreambooth_lora_krea2.py and the
Krea2LoraLoaderMixin (Krea2Pipeline now inherits it) so LoRA adapters
can be saved/loaded for the Krea 2 transformer. The transformer/pipeline
forward now accept attention_kwargs for runtime LoRA scaling.
Co-Authored-By: linoytsaban <linoy.tsaban@gmail.com>
* inline _pack/_unpack_latents in trainer (pipeline methods are instance methods)
* add Krea2LoraLoaderMixin to LoRA loaders docs
* remove mu from validation call to align with pipeline on main
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Co-authored-by: linoytsaban <linoy.tsaban@gmail.com>
Co-authored-by: Linoy Tsaban <57615435+linoytsaban@users.noreply.github.com>
