dashboard: transient_set / transient_cleared mutation events + client derived state

hive-c0re/src/coordinator.rs

@@ -105,6 +105,21 @@ pub enum TransientKind {
     Destroying,
 }
 
+impl TransientKind {
+    /// Wire/UI label. Matches the strings the dashboard already
+    /// renders in the transient spinner.
+    pub fn as_str(self) -> &'static str {
+        match self {
+            TransientKind::Spawning => "spawning",
+            TransientKind::Starting => "starting",
+            TransientKind::Stopping => "stopping",
+            TransientKind::Restarting => "restarting",
+            TransientKind::Rebuilding => "rebuilding",
+            TransientKind::Destroying => "destroying",
+        }
+    }
+}
+
 impl Coordinator {
     pub fn open(
         db_path: &Path,
@@ -318,10 +333,30 @@ impl Coordinator {
                 since: std::time::Instant::now(),
             },
         );
+        // Live-update dashboards. `since_unix` is wall-clock so the
+        // browser can tick "Ns spawning…" without polling. The
+        // intra-process map keeps using `Instant` for monotonicity.
+        let since_unix = std::time::SystemTime::now()
+            .duration_since(std::time::UNIX_EPOCH)
+            .ok()
+            .and_then(|d| i64::try_from(d.as_secs()).ok())
+            .unwrap_or(0);
+        self.emit_dashboard_event(DashboardEvent::TransientSet {
+            seq: self.next_seq(),
+            name: name.to_owned(),
+            transient_kind: kind.as_str(),
+            since_unix,
+        });
     }
 
     pub fn clear_transient(&self, name: &str) {
-        self.transient.lock().unwrap().remove(name);
+        let removed = self.transient.lock().unwrap().remove(name).is_some();
+        if removed {
+            self.emit_dashboard_event(DashboardEvent::TransientCleared {
+                seq: self.next_seq(),
+                name: name.to_owned(),
+            });
+        }
     }
 
     /// Set a transient state and return a guard that clears it on drop.

hive-c0re/src/dashboard_events.rs

@@ -105,4 +105,20 @@ pub enum DashboardEvent {
         answered_at: i64,
         cancelled: bool,
     },
+    /// A lifecycle action started for an agent (spawn / start / stop
+    /// / restart / rebuild / destroy). Clients render a spinner next
+    /// to the row; the client computes "seconds in this state"
+    /// locally from `since_unix` so a slow rebuild's elapsed time
+    /// ticks without polling.
+    TransientSet {
+        seq: u64,
+        name: String,
+        /// Lifecycle kind: `"spawning"` / `"starting"` / `"stopping"` /
+        /// `"restarting"` / `"rebuilding"` / `"destroying"`.
+        transient_kind: &'static str,
+        since_unix: i64,
+    },
+    /// The matching lifecycle action resolved (success or failure).
+    /// Clients drop the spinner row.
+    TransientCleared { seq: u64, name: String },
 }