refactor: extract parseClassList to shared utils

static/utils.ts

@@ -0,0 +1,10 @@
+export const parseClassList = (value: string | null): string[] => {
+  if (!value) {
+    return []
+  }
+
+  return value
+    .split(' ')
+    .map((entry: string): string => entry.trim())
+    .filter((entry: string): boolean => entry.length > 0)
+}