bugfix: a small refactor done in folder structure and naming conventions.

frontend/src/components/ui/shared/Checkbox.tsx

@@ -0,0 +1,70 @@
+'use client';
+
+import { useId } from 'react';
+import { Check } from 'lucide-react';
+
+type CheckboxProps = {
+  checked: boolean;
+  onChange: (checked: boolean) => void;
+  disabled?: boolean;
+  label: string;
+  id?: string;
+  className?: string;
+};
+
+/**
+ * App design-system checkbox: primary fill when checked, rounded, focus-visible ring.
+ */
+export function Checkbox({
+  checked,
+  onChange,
+  disabled = false,
+  label,
+  id,
+  className = '',
+}: CheckboxProps) {
+  const genId = useId();
+  const inputId = id ?? genId;
+
+  return (
+    <label
+      htmlFor={inputId}
+      className={`
+        inline-flex items-center gap-2.5 cursor-pointer select-none rounded-[var(--radius-sm)] -m-0.5 p-0.5
+        has-[:focus-visible]:ring-2 has-[:focus-visible]:ring-primary/45 has-[:focus-visible]:ring-offset-2
+        has-[:focus-visible]:ring-offset-background-secondary
+        ${disabled ? 'opacity-50 cursor-not-allowed' : ''}
+        ${className}
+      `}
+    >
+      <input
+        id={inputId}
+        type="checkbox"
+        className="sr-only"
+        checked={checked}
+        disabled={disabled}
+        onChange={(e) => onChange(e.target.checked)}
+      />
+      <span
+        className={`
+          flex h-5 w-5 shrink-0 items-center justify-center rounded-[var(--radius-sm)] border-2 transition-all duration-200
+          shadow-[inset_0_1px_0_rgba(255,255,255,0.05)]
+          ${
+            checked
+              ? 'border-primary bg-primary shadow-[0_0_0_1px_rgba(9,169,188,0.25)]'
+              : 'border-border-strong bg-background-card/90 hover:border-border'
+          }
+        `}
+        aria-hidden
+      >
+        <Check
+          strokeWidth={3}
+          className={`h-3.5 w-3.5 text-primary-contrast transition-all duration-200 ${
+            checked ? 'scale-100 opacity-100' : 'scale-75 opacity-0'
+          }`}
+        />
+      </span>
+      <span className="text-sm text-text-secondary">{label}</span>
+    </label>
+  );
+}