Improve error handling during request validation in BaseSession#774

painkiller90 wants to merge 1 commit intomodelcontextprotocol:v1.7.xmodelcontextprotocol/python-sdk:v1.7.xfrom

painkiller90:fix-request-try-wrappainkiller90/python-sdk:fix-request-try-wrapCopy head branch name to clipboard