Show thinking status for friends' Bots (DM peer Bot, face-room members on other homes) #297

Product ask: other people's Bots must show a "thinking…" status in FlyBot, like the user's own Bots do — in a direct chat with a friend's Bot and in a face-to-face room for Bots on other homes.

Findings

Own Bots today. The host knows a local turn is running (workView() / roomWorkView() in core/src/host/turns.js, sent to the client as work on the channel). The client draws it as the activity row at the transcript tail (activity-row.js, Shimmer + BotMark), MemberDock above a group composer (member-status.js), and "X is typing…" inside a group round (cells.js GroupReplies).

Remote Bots today. Nothing. A friend's Bot is a hidden chat Session whose model route (flybot-remote) calls no model, so the user's side never sees a "turn". Face-room members on other homes are only names in the participant list. The only signal is the message when it finally arrives. Bot Social has no presence/typing event (its inbox and face-room events are persisted messages and membership only), so the friend's home cannot tell us even if it wanted to.

Design

Two small, additive PRs, Bot Social first (see Birfy/bot-social#11):

1. Bot Social: ephemeral set_presence / list_presence (MCP + REST), TTL'd, rate limited, scoped to an active relationship or an open room, no content, presence in /v1/platform features.
2. FlyBot (plugins/social):
   • Send: on a local turn.start of a Bot whose trigger is a friend's line (direct) or that runs in a face room, send thinking (heartbeat every 10 s while the turn runs), idle on turn.end. Only when the server lists presence, and never for a read-only host.
   • Receive: the host polls list_presence (2.5 s) only while a social chat is open and shows it; a friend's message clears the entry at once; TTL otherwise.
   • UI: one small dock line above the composer: Name is thinking… (bt-shimmer, same type as the activity row), scoped to that chat or room. Nothing when the server has no feature.

Permissions are unchanged: the signal travels only between Bots that may already talk (relationship or room), carries only the Bot handle and state, and the owner's grants/approvals are not involved or bypassed.

Test

Two homes against one Bot Social: friend asks the Bot something, the asker sees Name is thinking… until the reply lands. Against an old server nothing is sent or shown.