chore: create frontend project from boilerplate

frontend/src/components/ai-elements/connection.tsx

@@ -0,0 +1,28 @@
+import type { ConnectionLineComponent } from "@xyflow/react";
+
+const HALF = 0.5;
+
+export const Connection: ConnectionLineComponent = ({
+  fromX,
+  fromY,
+  toX,
+  toY,
+}) => (
+  <g>
+    <path
+      className="animated"
+      d={`M${fromX},${fromY} C ${fromX + (toX - fromX) * HALF},${fromY} ${fromX + (toX - fromX) * HALF},${toY} ${toX},${toY}`}
+      fill="none"
+      stroke="var(--color-ring)"
+      strokeWidth={1}
+    />
+    <circle
+      cx={toX}
+      cy={toY}
+      fill="#fff"
+      r={3}
+      stroke="var(--color-ring)"
+      strokeWidth={1}
+    />
+  </g>
+);