ci: benchmark with Boost 1.84.0

🤖 Generated with [Claude Code](https://claude.ai/code)
Co-Authored-By: Claude <[email protected]>

Author: art049

CMakeLists.txt

@@ -12,7 +12,7 @@ endif()
 set(CMAKE_CXX_STANDARD 17)
 set(CMAKE_CXX_STANDARD_REQUIRED ON)
 if(NOT DEFINED BOOST_VERSION)
-  set(BOOST_VERSION "1.85.0")
+  set(BOOST_VERSION "1.84.0")
 endif()