Add modular pipeline for HunyuanVideo 1.5 (#13389)
* Add modular pipeline support for HunyuanVideo 1.5
* Fix I2V latent/cond spatial dimension mismatch
* Fix guidance_scale default to 7.5 matching ClassifierFreeGuidance
* Fix tokenizer type: use Qwen2TokenizerFast to match model
* Fix system message string formatting to match standard pipeline
* Rewrite HunyuanVideo 1.5 modular: use standard pipeline methods directly
* Remove I2V exports (T2V only for now)
* Fix encoder: use static methods directly instead of encode_prompt
* Inline all standard pipeline methods, remove runtime dependency
* Add HunyuanVideo 1.5 image-to-video modular blocks
* Fix missing FrozenDict import in before_denoise.py
* auto-generated docstrings via #auto_docstring
* Fix ruff lint and format issues
* use InputParam/OutputParam templates and fix ruff
* Address LTX review feedback here like add AutoBlocks, refactor I2V latents, lift encoders
* Add workflow map, workflow tests, auto docstrings, export only AutoBlocks
* Address Claude CI review
* Address claude CI review 2
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Co-authored-by: YiYi Xu <yixu310@gmail.com>
