Added small color preview

src/editor/components/nodetypeentry.css

@@ -10,3 +10,10 @@ div#ks-editor input {
 div#ks-editor .node-type-color {
     margin-bottom: 1em;
 }
+
+div#ks-editor .color-circle {
+    width: 15px;
+    height: 15px;
+    margin: 10px;
+    border-radius: 50%;
+}

src/editor/components/nodetypeentry.tsx

 import React, { useState } from "react";
 import { ColorData, NodeType, NodeTypeData } from "../../common/graph/nodetype";
+import { colorToRGB } from "../../common/helpers";
 import "./nodetypeentry.css";
 
 type NodeTypeEntryProps = {
@@ -97,6 +98,12 @@ function NodeTypeEntry({
                 value={nodeType.color.b.toString()}
                 onChange={(event) => handleColorChange("b", event.target.value)}
             />
+            <div
+                className={"color-circle"}
+                style={{
+                    backgroundColor: colorToRGB(nodeType.color),
+                }}
+            ></div>
             <br />
             <button onClick={() => onNodeTypeSelect(nodeType)}>
                 Select nodes