refactor(server/utils): isDev move to utils and replace fn with boolean

this value cannot change during runtime,
=> there is no need to have these checks
as dynamic function, instead just
export the boolean value directly

src/services/app_path.ts

@@ -1,4 +1,4 @@
 import assetPath from "./asset_path.js";
-import env from "./env.js";
+import { isDev } from "./utils.js";
 
-export default env.isDev() ? assetPath + "/app" : assetPath + "/app-dist";
+export default isDev ? assetPath + "/app" : assetPath + "/app-dist";