Parsing 100MB+ JSON Payloads with Web Workers

Parsing massive JSON files directly on the main thread causes UI freezing, dropped frames, and poor Core Web Vitals (Interaction to Next Paint - INP).

1. Web Worker Thread Offloading

By delegating JSON.parse() and AST serialization to a dedicated background Worker, the main-thread event loop remains completely responsive.

// worker-formatter.js
self.onmessage = function (e) {
  try {
    const parsed = JSON.parse(e.data);
    const formatted = JSON.stringify(parsed, null, 2);
    self.postMessage({ status: 'success', result: formatted });
  } catch (err) {
    self.postMessage({ status: 'error', message: err.message });
  }
};