Add FluxPAGPipeline with support for PAG

[tongyu0924]

What does this PR do?

This PR adds support for Perturbed Attention Guidance (PAG) to the FluxPipeline

Fixes #11488

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[DN6]

@tongyu0924 Is this ready for review? If so, could you move the pipeline under src/diffusers/pipelines/pag please and make the changes needed to import the pipeline?

[tongyu0924]

@tongyu0924 Is this ready for review? If so, could you move the pipeline under src/diffusers/pipelines/pag please and make the changes needed to import the pipeline?

Done! The pipeline is now under src/diffusers/pipelines/pag. It's ready for review

[DN6]

Thank you @tongyu0924 👍🏽! Could we add the pipeline to the necessary init files

PAG Module:
https://github.com/huggingface/diffusers/blob/main/src/diffusers/pipelines/pag/__init__.py

Pipelines Module:

diffusers/src/diffusers/pipelines/__init__.py

Line 175 in 049082e

_import_structure["pag"].extend(

Diffusers main init

diffusers/src/diffusers/__init__.py

Line 341 in 049082e

"AnimateDiffPAGPipeline",

And then could you please add a fast test for the pipeline, similar to how it has been done here

diffusers/tests/pipelines/pag/test_pag_sd3.py

Line 26 in 049082e

class StableDiffusion3PAGPipelineFastTests(unittest.TestCase, PipelineTesterMixin):

[tongyu0924]

Thank you @tongyu0924 👍🏽! Could we add the pipeline to the necessary init files

PAG Module: https://github.com/huggingface/diffusers/blob/main/src/diffusers/pipelines/pag/__init__.py

Pipelines Module:

diffusers/src/diffusers/pipelines/__init__.py

Line 175 in 049082e

_import_structure["pag"].extend(

Diffusers main init

diffusers/src/diffusers/__init__.py

Line 341 in 049082e

"AnimateDiffPAGPipeline",

And then could you please add a fast test for the pipeline, similar to how it has been done here

diffusers/tests/pipelines/pag/test_pag_sd3.py

Line 26 in 049082e

class StableDiffusion3PAGPipelineFastTests(unittest.TestCase, PipelineTesterMixin):

I've added the pipeline to the necessary __init__.py files and added a fast test following the structure in test_pag_sd3.py.