Tweaks to showing new version available

- Added frontend translation for english
- Moved frontend api logic to hook and backend api space
- Added swagger schema for the new api endpoint
- Moved backend logic to its own internal file
- Added user agent header to github api check
- Added cypress integration test for version check api
- Added a memory cache item from github check to avoid hitting it too
  much

frontend/src/api/backend/checkVersion.ts

@@ -0,0 +1,8 @@
+import * as api from "./base";
+import type { VersionCheckResponse } from "./responseTypes";
+
+export async function checkVersion(): Promise<VersionCheckResponse> {
+	return await api.get({
+		url: "/version/check",
+	});
+}