[core] FreeNoise (#8948)
* initial work draft for freenoise; needs massive cleanup
* fix freeinit bug
* add animatediff controlnet implementation
* revert attention changes
* add freenoise
* remove old helper functions
* add decode batch size param to all pipelines
* make style
* fix copied from comments
* make fix-copies
* make style
* copy animatediff controlnet implementation from #8972
* add experimental support for num_frames not perfectly fitting context length, ocntext stride
* make unet motion model lora work again based on #8995
* copy load video utils from #8972
* copied from AnimateDiff::prepare_latents
* address the case where last batch of frames does not match length of indices in prepare latents
* decode_batch_size->vae_batch_size; batch vae encode support in animatediff vid2vid
* revert sparsectrl and sdxl freenoise changes
* revert pia
* add freenoise tests
* make fix-copies
* improve docstrings
* add freenoise tests to animatediff controlnet
* update tests
* Update src/diffusers/models/unets/unet_motion_model.py
* add freenoise to animatediff pag
* address review comments
* make style
* update tests
* make fix-copies
* fix error message
* remove copied from comment
* fix imports in tests
* update
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Co-authored-by: Dhruv Nair <dhruv.nair@gmail.com>
