sendMessageDraft (Bot API 9.5) only works in private chats. Group,
supergroup and channel peers reject it with TEXTDRAFT_PEER_INVALID,
so Redstone was silently failing the entire reply path in groups
after the streaming feature landed in cab5337.
Keep replyWithStream for private chats (the typing animation is
the whole point); fall back to plain ctx.reply() everywhere else.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>