[config only] enable sourcemapping in production (#1666)

next.config.js

@@ -28,6 +28,7 @@ config = withTM({
   pageExtensions: ['mdx', 'md', 'jsx', 'tsx', 'api.ts'], // .ts files are not pages
 
   reactStrictMode: true,
+  productionBrowserSourceMaps: true,
 
   env: {
     MAIN_VIEW_SHOW_MAX_TOP_TOKENS_NUM:

tsconfig.json

@@ -1,5 +1,6 @@
 {
   "compilerOptions": {
+    "sourceMap": true,
     "baseUrl": ".",
     "target": "es6",
     "lib": ["dom", "dom.iterable", "esnext"],