feat: save graph to localstore

frontend/src/lib/components/graph/Graph.svelte

@@ -524,7 +524,7 @@
 
         $edges = $edges;
       });
-      graph.history.save();
+      graph.save();
     } else if ($hoveredSocket && $activeSocket) {
       if (
         typeof $hoveredSocket.index === "number" &&
@@ -547,7 +547,7 @@
           $hoveredSocket.index,
         );
       }
-      graph.history.save();
+      graph.save();
     }
 
     mouseDown = null;

frontend/src/lib/components/graph/GraphView.svelte

@@ -5,7 +5,7 @@
   import Node from "../Node.svelte";
   import { getContext, onMount } from "svelte";
   import type { Writable } from "svelte/store";
-  import { activeSocket, colors } from "./stores";
+  import { activeSocket } from "./stores";
 
   export let nodes: Writable<Map<number, NodeType>>;
   export let edges: Writable<EdgeType[]>;