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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❌ 2 New Failures, 1 Unrelated Failure, 1 Unclassified Failure

As of commit 1d5e805 with merge base 6edd49d ():

NEW FAILURES - The following jobs have failed:

• pull / unittest / linux / linux-job (gh)
  RuntimeError: Command docker exec -t 60e213652a44f9547ea2c336655b418684f68d0c836af25816730dbde2d008f9 /exec failed with exit code 1
• pull / unittest-editable / linux / linux-job (gh)
  RuntimeError: Command docker exec -t 975c99ff5362cc26d4dea22d782881a2cd2d58dd328735c1a5c441e2a97b950e /exec failed with exit code 1

UNCLASSIFIED FAILURE - DrCI could not classify the following job because the workflow did not run on the merge base. The failure may be pre-existing on trunk or introduced by this PR:

• periodic / gather-models (gh) (this job did not run on the merge base, so DrCI cannot tell whether the failure is pre-existing)

BROKEN TRUNK - The following job failed but were present on the merge base:

👉 Rebase onto the `viable/strict` branch to avoid these failures

• pull / unittest-nxp-neutron / linux-job (gh) (trunk failure)
  ##[error]The operation was canceled.

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[swha815]

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