When the agent sends a short single-chunk response (e.g. "Yep."), the
streaming edit path sends it to the channel immediately but never sets
sentAnyMessage. When finalizeMessage() then tries to edit the message
to identical content, Telegram rejects it ("message not modified"),
the catch swallows the error, and the post-loop fallback shows a
spurious "(No response)" error alongside the actual reply.
Fix: (1) set sentAnyMessage when the streaming path sends a new message,
(2) treat edit failures as success when messageId exists (the message
is already displayed to the user).
Written by Cameron ◯ Letta Code
"The stream carried everything -- we just forgot to look." - on debugging
5200a1e7e8