Adds trash icon button in Messages header that clears all communications
for the active group: DMs, channel messages, activity feed, seen tracking,
and dead letters. Shows Tauri warning dialog with confirmation before delete.
- Rust: clear_all_communications() in btmsg.rs (4 DELETE queries)
- Tauri command: btmsg_clear_all_comms
- Bridge: clearAllComms(groupId)
- UI: trash button with hover-red styling, resets all local state after clear
Green borders in GroupAgentsPanel and health dots stayed active after
stopping agents because btmsg DB status was never set to 'stopped'.
- Add terminal state guard in agent store (done/error cannot revert to active)
- Optimistic updateAgentStatus('done') on all stop paths (AgentPane, StatusBar Stop All, AgentSession onAgentStop)
- Sync btmsg agent status to 'stopped' in agent-dispatcher on every terminal transition (agent_stopped, agent_error, cost done/error, sidecar crash)
- Sync btmsg optimistically in UI stop handlers for immediate card border update
- Add Stop All button to StatusBar with wake scheduler kill
