feat(maestro): clear AwaitingInput glow once a pane has been focused

A session's rail glows AwaitingInput even after the operator has already
looked at it. Clients now report pane focus (POST /:id/focus); the daemon
clears the glow to Idle after 5s of continuous focus and keeps it cleared
until the session does new work, so a fresh Active cycle is required to
glow again.

crates/maestro-daemon/src/session.rs

@@ -71,6 +71,15 @@ pub struct SessionRecord {
     /// (#115), so this is the observable that says its outcomes are safe to
     /// assert on. Daemon-local bookkeeping; never rides the wire.
     pub settled: bool,
+    /// When a client's pane last became the one showing this session
+    /// (`POST /.../focus`), `None` while unfocused. Daemon-local; never rides
+    /// the wire.
+    pub focused_since: Option<std::time::Instant>,
+    /// Sticky acknowledgement applied by [`crate::activity::apply_focus_suppression`]:
+    /// once the pane has been focused long enough to clear an `AwaitingInput`
+    /// glow, this holds through focus loss until the session does new work.
+    /// Daemon-local; never rides the wire.
+    pub awaiting_suppressed: bool,
 }
 
 #[derive(Debug, thiserror::Error)]
@@ -456,6 +465,8 @@ impl SessionManager {
                     bridge,
                     reported_activity: None,
                     settled: false,
+                    focused_since: None,
+                    awaiting_suppressed: false,
                 },
             );
         }
@@ -659,6 +670,8 @@ impl SessionManager {
                     bridge,
                     reported_activity: None,
                     settled: false,
+                    focused_since: None,
+                    awaiting_suppressed: false,
                 },
             );
             let _ = self
@@ -799,6 +812,17 @@ impl SessionManager {
         }
         Ok(())
     }
+
+    /// Record whether a client's pane is currently showing `id`. Read by the
+    /// activity pass's next tick to decide whether an `AwaitingInput` glow
+    /// has been looked at long enough to clear (`apply_focus_suppression`).
+    /// An unknown session is [`SessionError::NotFound`].
+    pub async fn set_focused(&self, id: Uuid, focused: bool) -> Result<(), SessionError> {
+        let mut sessions = self.inner.sessions.lock().await;
+        let rec = sessions.get_mut(&id).ok_or(SessionError::NotFound(id))?;
+        rec.focused_since = focused.then(std::time::Instant::now);
+        Ok(())
+    }
 }
 
 /// Run a blocking `tmux` subprocess call on the blocking thread pool so it
@@ -955,10 +979,19 @@ async fn run_activity_pass(inner: &Arc<Inner>) {
             // #105: while a report is in force it supplies the state and
             // nothing here may overwrite it; only an unreported session is
             // decided by inference.
-            let activity = match &rec.reported_activity {
+            let raw_activity = match &rec.reported_activity {
                 Some(report) => report.state,
                 None => crate::activity::decide(idle, awaiting),
             };
+            // A pane looked at long enough clears an `AwaitingInput` glow
+            // (docs/SIDEBAR.md); the acknowledgement is sticky until the
+            // session does new work again.
+            let activity = crate::activity::apply_focus_suppression(
+                raw_activity,
+                rec.focused_since,
+                std::time::Instant::now(),
+                &mut rec.awaiting_suppressed,
+            );
             let foreground = Some(pane.command.clone());
             // The pane's live cwd, drives the dir-based session tree; empty means
             // tmux reported none.