fix(message): correctly concat base64-encoded data block deltas#31

DavdGao merged 2 commits into

agentscope-ai:mainagentscope-ai/agentscope-typescript:mainfrom

qbc2016:bc/data-block-delta-concat-fiqbc2016/agentscope-typescript:bc/data-block-delta-concat-fiCopy head branch name to clipboard