feat: sidebar badge on new game download option

src/main/level/sublevels/downloadSourcesCheckTimestamp.ts

@@ -0,0 +1,16 @@
+import { levelKeys } from "./keys";
+import { db } from "../level";
+
+export const getLastDownloadSourcesCheck = async (): Promise<string | null> => {
+  try {
+    const timestamp = await db.get(levelKeys.lastDownloadSourcesCheck);
+    return timestamp;
+  } catch (error) {
+    // Key doesn't exist yet
+    return null;
+  }
+};
+
+export const updateLastDownloadSourcesCheck = async (timestamp: string): Promise<void> => {
+  await db.put(levelKeys.lastDownloadSourcesCheck, timestamp);
+};