gai: Misc cleanup and refactoring in gai client.

gai-frontend/lib/chat/callout_painter.dart

@@ -0,0 +1,37 @@
+import 'package:orchid/orchid/orchid.dart';
+
+class CalloutPainter extends CustomPainter {
+  @override
+  void paint(Canvas canvas, Size size) {
+    final paint = Paint()
+      ..color = Colors.white.withOpacity(0.8)
+      ..style = PaintingStyle.stroke
+      ..strokeWidth = 1.5;
+
+    const radius = 10.0; // Corner radius
+    const calloutWidth = 25.0;
+    const calloutHeight = 20.0;
+    final calloutStart =
+        size.width - 115.0; // Adjust this to position the callout
+
+    final path = Path()
+      ..moveTo(radius, 0)
+      ..lineTo(calloutStart, 0)
+      ..lineTo(calloutStart + (calloutWidth / 2), -calloutHeight)
+      ..lineTo(calloutStart + calloutWidth, 0)
+      ..lineTo(size.width - radius, 0)
+      ..quadraticBezierTo(size.width, 0, size.width, radius)
+      ..lineTo(size.width, size.height - radius)
+      ..quadraticBezierTo(
+          size.width, size.height, size.width - radius, size.height)
+      ..lineTo(radius, size.height)
+      ..quadraticBezierTo(0, size.height, 0, size.height - radius)
+      ..lineTo(0, radius)
+      ..quadraticBezierTo(0, 0, radius, 0);
+
+    canvas.drawPath(path, paint);
+  }
+
+  @override
+  bool shouldRepaint(CustomPainter oldDelegate) => false;
+}