Refactor PartitionsSaxHandler to use boost::json #2230

Job	Run time
PSV.Linux.22.04.gcc9.Tests.CodeCov	11m 13s
PSV.iOS.MacOS14.Xcode15.ARM64	6m 5s
PSV.Linux.latest.gcc14.OLP_SDK_ENABLE_DEFAULT_CACHE=OFF	2m 37s
PSV.iOS.MacOS15.Xcode26.ARM64	6m 16s
PSV.Commit.Checker	6s
PSV.MacOS15.Xcode16.ARM64	6m 0s
PSV.Linux.24.04.gcc13.Tests	8m 7s
PSV.iOS.MacOS15.Xcode16.ARM64	7m 51s
PSV.Linux.22.04.clang	9m 44s
PSV.Win.VC2022	10m 53s
PSV.Linux.22.04.gcc9.Cpplint	8m 48s
PSV.Linux.22.04.gcc11	8m 46s
PSV.Linux.22.04.gcc11.OLP_SDK_NO_EXCEPTION=ON	7m 14s
PSV.Linux.22.04.gcc11.OLP_SDK_ENABLE_DEFAULT_CACHE=OFF	3m 2s
PSV.Linux.Android.22.04	6m 17s
PSV.Clang.Format.Checker	32s
PSV.Linux.22.04.gcc9.OLP_SDK_ENABLE_DEFAULT_CACHE=OFF	2m 47s
	1h 46m 18s

Provide feedback