refactor(web_ui): Bus::effective_context_window, sigint_claude + per-connection hello, relocate fetch_reminder_stats, drop redundant guard

hive-ag3nt/src/web_ui/stream.rs

@@ -56,15 +56,22 @@ pub(super) async fn events_stream(
 ) -> Sse<impl Stream<Item = Result<Event, Infallible>>> {
     tracing::info!("sse: client subscribed");
     let rx = state.bus.subscribe();
-    // Drop a "hello" note into the bus so every new subscriber sees at
-    // least one event immediately and can clear the connecting placeholder.
-    state.bus.emit(crate::events::LiveEvent::Note {
-        text: "live stream attached".into(),
-    });
-    let stream = BroadcastStream::new(rx).filter_map(|res| {
+    // Prime THIS connection with a one-off "hello" so it can clear the
+    // connecting placeholder immediately. Injected into this subscriber's own
+    // stream rather than emitted to the bus — a bus emit would spam every
+    // already-connected client with a spurious note each time anyone opens
+    // the stream.
+    let hello = Event::default().data(
+        serde_json::to_string(&crate::events::LiveEvent::Note {
+            text: "live stream attached".into(),
+        })
+        .unwrap_or_default(),
+    );
+    let live = BroadcastStream::new(rx).filter_map(|res| {
         let ev = res.ok()?;
         let json = serde_json::to_string(&ev).ok()?;
         Some(Ok(Event::default().data(json)))
     });
+    let stream = tokio_stream::once(Ok(hello)).chain(live);
     Sse::new(stream).keep_alive(KeepAlive::default())
 }