rebuild_queue: wire worker into coordinator + dashboard event

hive-c0re/src/dashboard_events.rs

@@ -27,6 +27,7 @@ use serde::Serialize;
 
 use crate::container_view::ContainerView;
 use crate::dashboard::{MetaInputView, TombstoneView};
+use crate::rebuild_queue::QueueEntry;
 
 #[derive(Debug, Clone, Serialize)]
 #[serde(rename_all = "snake_case", tag = "kind")]
@@ -204,4 +205,16 @@ pub enum DashboardEvent {
     /// when the active-run count crosses 0, so concurrent updates flip
     /// the flag exactly once.
     MetaUpdateRunning { seq: u64, running: bool },
+    /// Full snapshot of the rebuild queue (`hive-c0re::rebuild_queue`)
+    /// — every entry, in enqueue order, including the few most-recent
+    /// terminal entries the queue retains for history. Same
+    /// snapshot-shape rationale as `TombstonesChanged` /
+    /// `MetaInputsChanged`: the list is small, snapshot semantics avoid
+    /// the add/remove races a per-row event would have, and the
+    /// dashboard's grouping (parent_id) is most naturally re-derived
+    /// from the full list.
+    RebuildQueueChanged {
+        seq: u64,
+        queue: Vec<QueueEntry>,
+    },
 }