improvement: toast component created and used every where in the app.

frontend/src/components/ui/common/Toast.tsx

@@ -0,0 +1,26 @@
+import type { ReactNode } from 'react';
+import type { BadgeVariant } from '@/components/ui/common/Badge';
+
+interface ToastProps {
+  children: ReactNode;
+  variant?: BadgeVariant;
+  className?: string;
+}
+
+const variantStyles: Record<BadgeVariant, string> = {
+  success: 'bg-badge-success-bg text-badge-success-fg border-badge-success-border',
+  warning: 'bg-badge-warning-bg text-badge-warning-fg border-badge-warning-border',
+  danger: 'bg-badge-danger-bg text-badge-danger-fg border-badge-danger-border',
+  default: 'bg-badge-default-bg text-badge-default-fg border-badge-default-border',
+};
+
+export function Toast({ children, variant = 'default', className = '' }: ToastProps) {
+  return (
+    <div
+      role="status"
+      className={`w-full rounded-[var(--radius-md)] border px-4 py-3 text-sm shadow-lg ${variantStyles[variant]} ${className}`}
+    >
+      {children}
+    </div>
+  );
+}