fix(persistence): deep-copy snapshot in load_next to keep history immutable#3077

lienminhquang wants to merge 4 commits intopydantic:mainpydantic/pydantic-ai:mainfrom

lienminhquang:Fix-state-in-snapshot-of-FullStatePersistence's-history-is-multablelienminhquang/pydantic-ai:Fix-state-in-snapshot-of-FullStatePersistence's-history-is-multableCopy head branch name to clipboard