Refactor PartitionsSaxHandler to use boost::json #2236

Job	Run time
PSV.Linux.22.04.gcc11	8m 48s
PSV.Linux.latest.gcc14.OLP_SDK_ENABLE_DEFAULT_CACHE=OFF	5m 9s
PSV.Linux.22.04.gcc9.OLP_SDK_ENABLE_DEFAULT_CACHE=OFF	2m 44s
PSV.Linux.22.04.gcc11.OLP_SDK_ENABLE_DEFAULT_CACHE=OFF	2m 41s
PSV.iOS.MacOS14.Xcode15.ARM64	6m 45s
PSV.iOS.MacOS15.Xcode16.ARM64	7m 4s
PSV.Commit.Checker	9s
PSV.Linux.22.04.gcc9.Tests.CodeCov	10m 33s
PSV.Linux.22.04.clang	9m 21s
PSV.Linux.22.04.gcc11.OLP_SDK_NO_EXCEPTION=ON	7m 37s
PSV.Linux.24.04.gcc13.Tests	8m 23s
PSV.Linux.Android.22.04	5m 52s
PSV.Linux.22.04.gcc9.Cpplint	9m 0s
PSV.MacOS15.Xcode16.ARM64	5m 11s
PSV.iOS.MacOS15.Xcode26.ARM64	6m 21s
PSV.Win.VC2022	9m 58s
PSV.Clang.Format.Checker	35s
	1h 46m 11s

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