Updates the Stan submodule to b83f95f1f.

stan-buildbot · stan-buildbot · commit e8f40e115353 · 2025-06-11T16:30:02.000-04:00
diff --git a/stan b/stan
@@ -1 +1 @@
-Subproject commit 59845f1ba9e6832da35a2f621549441b73384685
+Subproject commit b83f95f1f072b3d144161d61ea79fe4550b21573
