Add wrappers for Stable Diffusion 3.5 Large model

[FabulousSuperDude]

• Wrappers for CLIP/T5 text encoders, Transformer, and VAEDecoder contained in SD3.5 Large model.
• Support for exporting any or all of the above component output generated from dummy input (normal-distributed random values).

Change-Id: I3bc202e2e856a81c6598cf01cdcd8ec158694c25

[pytorch-bot]

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As of commit 903fcb2 with merge base 9b7fd14 ():

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[swha815]

Posting again to resolve credential problems with Github account. The original PR was closed without merging.