write @agent_state on attendance changes, not just transitions

the seen demotion (done -> idle when the user focuses the pane) only
updated the daemon's internal track; @agent_state stayed done forever,
so the menu bar and status line never reflected attendance. the display
status is now written whenever it differs from the pane option,
regardless of what triggered it.

1 files changed, 12 insertions, 4 deletions

diff --git a/crates/dinggerd/src/watcher.rs b/crates/dinggerd/src/watcher.rs
index 045fb64..f1cb90e 100644
--- a/crates/dinggerd/src/watcher.rs
+++ b/crates/dinggerd/src/watcher.rs
@@ -232,14 +232,22 @@ impl Watcher {
             }
             if transition {
                 debug!(target = %pane.display_target, ?prev_state, ?new_state, seen, "state change");
-                let display = display_status(&self.tracks[&pane.pane_id]);
-                if let Err(err) = tmux::set_agent_state(&pane.pane_id, display.label()) {
-                    warn!(target = %pane.display_target, %err, "failed to write @agent_state");
-                }
                 let _ = tmux::clear_ack(&pane.pane_id);
             } else if seen != prev_seen {
                 let _ = tmux::ack(&pane.pane_id);
             }
+            let display = display_status(
+                self.tracks
+                    .get(&pane.pane_id)
+                    .unwrap_or(&PaneTrack { state: new_state, seen, ready_since: None }),
+            );
+            // @agent_state mirrors the display status on both transitions and
+            // attendance changes (done → idle when the user focuses the pane).
+            if pane.written_state != display.label() {
+                if let Err(err) = tmux::set_agent_state(&pane.pane_id, display.label()) {
+                    warn!(target = %pane.display_target, %err, "failed to write @agent_state");
+                }
+            }
             if new_state == AgentState::Unknown {
                 // The agent is gone; its last hook report must not outlive it.
                 hooks::drop_report(&pane.pane_id);