{Build} Core - Bump VRS pin for XPRS NVDEC symbols

Summary:
Explanation:
`projectaria_tools` builds VRS via `FetchContent` with a pinned `GIT_TAG` in
`cmake/Setup3rdParty.cmake`. The previous pin (`125db715`, main Jun 26, 2026)
predates the XPRS NVDEC changes, so `core/python/XprsPyBind.h` references
`xprs::hasCudaSupport` while the fetched VRS does not declare it. The external
wheel build fails with:

```
core/python/XprsPyBind.h:152:14: error: no member named 'hasCudaSupport' in namespace 'xprs'
      &xprs::hasCudaSupport,
```

This bumps the VRS pin to `15d40a41b107f7923f6368b93109919cd49bb3c9`, which
carries the NVDEC symbols (`xprs::hasCudaSupport` plus the `ENABLE_NVCODEC`
plumbing), unblocking NVDEC in the wheel build.

Reproducibility:
`arc f` and `arc lint` pass on the changed file. The pinned commit resolves in
`facebookresearch/vrs`, so `FetchContent` can fetch it and the wheel build can
compile `XprsPyBind.h`.

Differential Revision: D114445000

Author: YLouWashU

cmake/Setup3rdParty.cmake

@@ -37,10 +37,14 @@ FetchContent_Declare(
 )
 
 # Fetch VRS lib with XPRS support
+# The pin must carry the XPRS NVDEC symbols (xprs::hasCudaSupport plus the
+# ENABLE_NVCODEC plumbing); the previous pin (125db715) predates them, so
+# XprsPyBind.h fails to compile with "no member named 'hasCudaSupport' in
+# namespace 'xprs'".
 FetchContent_Declare(
   vrs
   GIT_REPOSITORY https://github.com/facebookresearch/vrs.git
-  GIT_TAG 125db715b73e2768723defcb88ccb755fabcd43d # main Jun 26, 2026.
+  GIT_TAG 15d40a41b107f7923f6368b93109919cd49bb3c9 # XPRS NVDEC support.
 )
 # Override config for vrs
 option(UNIT_TESTS OFF)