feature: add store for tracking network request to API

lib/frontend/records/index.js

@@ -0,0 +1,5 @@
+import Request from './request'
+
+export {
+  Request,
+}

lib/frontend/records/request.js

@@ -0,0 +1,9 @@
+export default class Request {
+  constructor({
+    id,
+    error,
+  }) {
+    this.id = id
+    this.error = error
+  }
+}

lib/frontend/stores/index.js

@@ -1,7 +1,9 @@
 import configStore from './configStore'
 import eventStore from './eventStore'
+import requestStore from './requestStore'
 
 export {
   configStore,
   eventStore,
+  requestStore,
 }

lib/frontend/stores/requestStore.js

@@ -0,0 +1,3 @@
+import { writable } from 'svelte/store'
+
+export default writable(null)