refactor: use mobx for state and separate files for components

app/assets/javascripts/preferences/panes/account/subscription/SubscriptionWrapper.tsx

@@ -0,0 +1,20 @@
+import { WebApplication } from '@/ui_models/application';
+import { FunctionalComponent } from 'preact';
+import { Subscription } from './Subscription';
+import { SubscriptionState } from './subscription_state';
+
+type Props = {
+  application: WebApplication;
+};
+
+export const SubscriptionWrapper: FunctionalComponent<Props> = ({
+  application,
+}) => {
+  const subscriptionState = new SubscriptionState();
+  return (
+    <Subscription
+      application={application}
+      subscriptionState={subscriptionState}
+    />
+  );
+};