feat(#1137): rich unread summary in loose ends and wake signal

- hive-sh4re: UnreadMatrix gains summary: String field (per-room breakdown)
- hive-matrix-mcp/protocol: add RoomUnread struct + UnreadSummary request
- hive-matrix-mcp/handlers: collect_unread() fetches per-room data;
  single-unread rooms include truncated last-message body + sender;
  multi-unread rooms carry count only
- hive-matrix-mcp/wake: format_unread_summary() builds wake body from
  RoomUnread slice; terse one-liner for single-room/single-message,
  bulleted list for multi-room; always appends read-hint
- hive-matrix-mcp/timeline: wake body now covers all rooms with unread
  at fire time, not just the triggering event; falls back to per-event
  teaser if notification counts haven't updated yet
- hive-ag3nt/mcp: matrix_unread_summary() replaces matrix_unread_rooms();
  UnreadMatrix loose end carries per-room summary lines; render shows
  room breakdown with sender: body for single-unread rooms

hive-ag3nt/src/web_ui.rs

@@ -319,10 +319,9 @@ async fn relay_ws_vnc(socket: axum::extract::ws::WebSocket, vnc_port: u16) {
     let ws_to_tcp = tokio::spawn(async move {
         while let Some(Ok(msg)) = futures_util::StreamExt::next(&mut ws_rx).await {
             match msg {
-                Message::Binary(data)
-                    if tcp_tx.write_all(&data).await.is_err() => {
-                        break;
-                    }
+                Message::Binary(data) if tcp_tx.write_all(&data).await.is_err() => {
+                    break;
+                }
                 Message::Close(_) => break,
                 _ => {} // ping/pong/text: ignore
             }