feat(nodes): add start node and create new node function

client/src/components/nodes/defaultHandleStyle.ts

@@ -1,7 +1,34 @@
-const DEFAULT_HANDLE_STYLE = {
+// horizontal
+const HANDLE_STYLE_CONNECTED = {
   width: 8,
   height: 8,
   backgroundColor: "#BDBDBD",
 };
 
-export default DEFAULT_HANDLE_STYLE;
+// horizontal
+const HANDLE_STYLE_DISCONNECTED = {
+  width: 20,
+  height: 20,
+  backgroundColor: "#C7D95A",
+  borderColor: "#606060",
+  borderWidth: 2,
+};
+
+// vertical
+const HANDLE_STYLE_CONNECTED_V = {
+  ...HANDLE_STYLE_CONNECTED,
+  right: "-4px",
+};
+
+// vertical
+const HANDLE_STYLE_DISCONNECTED_V = {
+  ...HANDLE_STYLE_DISCONNECTED,
+  right: "-10px",
+};
+
+export {
+  HANDLE_STYLE_CONNECTED,
+  HANDLE_STYLE_DISCONNECTED,
+  HANDLE_STYLE_CONNECTED_V,
+  HANDLE_STYLE_DISCONNECTED_V,
+};