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

cc @mergennachin @iseeyuan @lucylq @helunwencser @tarun292 @kimishpatel @jackzhxng @digantdesai @freddan80 @per @zingo @oscarandersson8218 @mansnils @Sebastian-Larsson @robell @rascani

[pytorch-bot]

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[github-actions]

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[swha815]

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

[zingo]

Not something that is needed and Im not sure if it makes sense for this model but when possible it's nice to add them to examples/models/init.py also then it's easier to test them with scripts in CI and such, but I see the non large stable diffusion is also missing and there might be a reason for this already.