refactor: moved delete logic out of the toolbar declaration and into the FlowStore.

BREAKING: changed type of FlowState

ref: N25B-114

src/pages/VisProgPage/visualProgrammingUI/VisProgStores.tsx

@@ -93,6 +93,12 @@ const useFlowStore = create<FlowState>((set, get) => ({
         edgeReconnectSuccessful: true
       });
     },
+    deleteNode: (nodeId: string) => {
+      set({
+        nodes: get().nodes.filter((n) => n.id !== nodeId),
+        edges: get().edges.filter((e) => e.source !== nodeId && e.target !== nodeId)
+      });
+    },
     setNodes: (nodes) => {
       set({nodes});
     },