hivectl: migrate dag_progress to hive-jobq-wire's generic GraphNode

hive-c0re/src/job_queue/mod.rs

@@ -378,6 +378,30 @@ impl JobQueue {
             .filter_map(|c| dag_view(&inner, c))
             .collect()
     }
+
+    /// One DAG's container node plus its live subtree, as generic wire
+    /// nodes — the `QueueNodes` polling surface behind `hivectl`'s
+    /// wait/progress loop. Sibling of [`Self::snapshot`]
+    /// (which serves the same graph through the typed `DagView`/`NodeView`
+    /// projection for the dashboard's `/api/state.rebuild_queue`), this one
+    /// goes through [`GraphWire::wire_snapshot`] instead — no `Done`-node
+    /// filtering, no roll-up field (the root's own `state` answers that,
+    /// see `hive_jobq_wire`'s doc comment).
+    ///
+    /// Empty when `dag_id` names no DAG container in the graph. Today that
+    /// only happens for a genuinely unknown id: nothing prunes the graph
+    /// yet (bounded-prune is a Stage-C follow-up, see [`visible_dags`]), so
+    /// a *completed* DAG's nodes keep riding here with a terminal `state`
+    /// rather than disappearing — callers watching for "done" should read
+    /// the root's `state`, not emptiness.
+    #[must_use]
+    pub fn dag_nodes(&self, dag_id: u64) -> Vec<GraphNode> {
+        let inner = self.lock();
+        let Some(root) = container(&inner, dag_id) else {
+            return Vec::new();
+        };
+        inner.graph().wire_snapshot([root])
+    }
 }
 
 /// The container node of `dag_id` — the `NodeKind::Dag` root whose id equals