fix: strip line number prefixes from all JS files

frontend/js/config.js

@@ -1,4 +1,4 @@
-1|// config.js — extracted from app.js (3872-4865)
+// config.js — extracted from app.js (3872-4865)
 import { state } from './state.js';
 
 let _recentTimestampTimer = null;