Add JSON preview for smart playlist query

src/renderer/features/shared/components/json-preview.tsx

@@ -0,0 +1,7 @@
+interface JsonPreviewProps {
+    value: string | Record<string, any>;
+}
+
+export const JsonPreview = ({ value }: JsonPreviewProps) => {
+    return <pre style={{ userSelect: 'all' }}>{JSON.stringify(value, null, 2)}</pre>;
+};