add apollo setup

app/javascript/contexts/ApolloContext.tsx

@@ -0,0 +1,36 @@
+import React, { FC } from "react";
+import {
+  ApolloClient,
+  createHttpLink,
+  InMemoryCache,
+  ApolloProvider,
+} from "@apollo/client";
+
+type Props = {
+  children: React.ReactNode
+}
+
+export const ApolloContext: FC<Props> = ({ children }) => {
+  const crfsToken = document
+    .querySelector("[name='csrf-token']")
+    ?.getAttribute('content')
+
+  if (!crfsToken) {
+    throw new Error('CSRF token not found')
+  }
+
+  const httpLink = createHttpLink({
+    uri: '/graphql',
+    headers: {
+      'X-CSRF-Token': crfsToken,
+    }
+  })
+
+  const client = new ApolloClient({
+    link: httpLink,
+    cache: new InMemoryCache(),
+    credentials: "same-origin",
+  });
+
+  return <ApolloProvider client={client}>{children}</ApolloProvider>;
+};