Add LTX-2.X IC LoRA and HDR Pipelines (#13572)
* LTX-2.X IC LoRA + HDR IC LoRA pipeline implementation draft from Claude
* Refactor HDR export to accept custom tone-mapping functions
* Apply parity fixes + refactor + allow HDR LoRA pipeline to accept connector embeddings
* Change LTX2ConditionPipeline default __call__ parameters to match the suggested params for the LTX-2.3 model
* Improve IC LoRA example and fix some LTX2ICLoraPipeline bugs
* Improve HDR IC LoRA example
* Clean up the code a bit
* make style and make quality
* Rename LTX2ICLoraPipeline to LTX2InContextPipeline and LTX2HDRLoraPipeline to LTX2HDRPipeline
* Improve LTX2InContextPipeline and LTX2HDRPipeline docstrings
* Add export function to directly convert HDR tensors to .mp4 files
* Clean up the code/docstrings some more
* Move new video_self_attention_mask LTX-2.X transformer arg to end to preserved positional arg ordering
* make fix-copies
* Simplify HDR export functions to only export to mp4
* Revert LTX2ConditionPipeline default __call__ values back to previous (LTX-2.0) defaults
* Inline simple_tone_map and linear_to_srgb into encoder_hdr_tensor_to_mp4 for HDR export
* Apply suggestions from review
* Refactor HDR video processor to handle output_type in postprocess_hdr_video
* Rewrite simple_tone_map as function rather than lambda since otherwise ruff complains
* make style and make quality
* Refactor HDR pipeline to use audio_scheduler as an optional component
* Add initial LTX2ConditionPipeline tests
* make style and make quality
* Add initial LTX2InContextPipeline tests
* Add initial LTX2HDRPipeline tests
* Try to fix failing tests for new LTX-2.X pipelines
* Propagate suggestions from HDR pipeline to IC and condition pipelines
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Co-authored-by: YiYi Xu <yixu310@gmail.com>
