[training ] add Kontext i2i training (#11858)
* feat: enable i2i fine-tuning in Kontext script.
* readme
* more checks.
* Apply suggestions from code review
Co-authored-by: Linoy Tsaban <57615435+linoytsaban@users.noreply.github.com>
* fixes
* fix
* add proj_mlp to the mix
* Update README_flux.md
add note on installing from commit `05e7a854d0a5661f5b433f6dd5954c224b104f0b`
* fix
* fix
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Co-authored-by: Linoy Tsaban <57615435+linoytsaban@users.noreply.github.com>
