[CI] Add Windows Blender test to nightly (#21718)
This PR introduces a real world test into CI.
The idea is we build and run Blender using the just-built SYCL compiler
(initially, only the nightly) and then run an example workflow on a
(multi) GPU system.
The first version of this PR only tracks pass/fail, but in the future we
could add a performance threshold to cause a fail.
First we build OIDN and Embree, both of which use SYCL and DPC++. Then
we build Blender with the just-built OIDN, Embree and SYCL compiler.
The steps of this workflow (as in, what to do at a high level) were
developed with help from internal Blender experts.
Run in nightly example:
https://github.com/intel/llvm/actions/runs/24317863959/job/70999916822
Entire workflow takes ~10 minutes.
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Signed-off-by: Nick Sarnie <nick.sarnie@intel.com>
