[Dashboard] display actor status and infeasible tasks (#6652)

* expose actor status and protobuf message of infeasible tasks

* move infeasible tasks into actor tree

* add pytest for displaying infeasible tasks info

* fix base64 decoding

* fix race condition after #6629 merged

src/ray/protobuf/node_manager.proto

@@ -87,6 +87,7 @@ message GetNodeStatsReply {
   map<string, double> available_resources = 3;
   map<string, double> total_resources = 4;
   uint32 num_workers = 5;
+  repeated TaskSpec infeasible_tasks = 6;
 }
 
 // Service for inter-node-manager communication.

src/ray/raylet/node_manager.cc

@@ -3018,6 +3018,10 @@ void NodeManager::HandleNodeStatsRequest(const rpc::GetNodeStatsRequest &request
       (*available_resources_map)[pair.first] = 0.0;
     }
   }
+  for (const auto task : local_queues_.GetTasks(TaskState::INFEASIBLE)) {
+    auto infeasible_task = reply->add_infeasible_tasks();
+    infeasible_task->ParseFromString(task.GetTaskSpecification().Serialize());
+  }
   // Ensure we never report an empty set of metrics.
   if (!recorded_metrics_) {
     RecordMetrics();