Add config loader tools

tools/config.ts

@@ -0,0 +1,16 @@
+export function loadConfig(path: string): Config | null {
+  const item = localStorage.getItem(path);
+  if (!item) {
+    return null;
+  }
+
+  try {
+    return JSON.parse(item) as Config;
+  } catch (e) {
+    return null;
+  }
+}
+
+export interface Config {
+	searchBar: boolean,
+}