After the agent's final response, the '...typing' bubble persisted ~5s.
send() re-triggers send_typing() after every delivery so the bubble
survives intermediate progress messages (Telegram clears typing on each
delivered message). But that re-trigger also fired on the FINAL send,
re-arming Telegram's ~5s timer AFTER the gateway had already torn down
its typing-refresh loop — and Telegram exposes no stop-typing API, so
nothing cancelled it.
Gate the post-send re-trigger on the absence of metadata['notify'] (set
only on the final user-visible reply via _mark_notify_metadata). Both
the rich-message and legacy send paths are covered; intermediate
progress sends still re-trigger so the bubble stays alive mid-response.
Fixes#48678
565b7c8d9d