added spotify auth callback

packages/app/src/pages/callbacks/sync/spotify/index.jsx

@@ -0,0 +1,35 @@
+import React from "react"
+
+import * as antd from "antd"
+
+import SyncModel from "models/sync"
+
+export default (props) => {
+    const [error, setError] = React.useState(null)
+
+    const makeSync = async () => {
+        const result = await SyncModel.spotifyCore.syncAuthCode(window.location.search.split("=")[1]).catch((err) => {
+            setError(err.message)
+
+            return false
+        })
+
+        if (result) {
+            window.close()
+        }
+    }
+
+    React.useEffect(() => {
+        makeSync()
+    }, [])
+
+    if (error) {
+        return <antd.Result
+            status="error"
+            title="Error while syncing your Spotify account"
+            subTitle={error}
+        />
+    }
+
+    return <h3>Please wait meanwhile we are syncing your Spotify account</h3>
+}