Update Shared and related NuGet packages to 2026.5.6 - #266

Update Shared and related NuGet packages to 2026.5.6#266

StuartFerguson merged 4 commits into

mainTransactionProcessing/CallbackHandler:mainfrom

task/#247_new_serialiserTransactionProcessing/CallbackHandler:task/#247_new_serialiserCopy head branch name to clipboard