JS bundle 612KB -> 188KB on a B2B dashboard

JS bundle 612KB -> 188KB on a B2B dashboard
Main bundle shipped a whole date library, a charting lib, and an icon set fully imported.
— moment.js (231KB) -> date-fns with 3 functions (8KB).
— Icon font (90KB) -> 12 inline SVGs (4KB).
— Charting lib code-split, loaded only on /analytics.
Gzipped transfer: 198KB -> 61KB. Main-thread parse/compile: 410ms -> 120ms.
— INP (Interaction to Next Paint) p75: 290ms -> 140ms.
Takeaway: 424KB removed, 290ms of main-thread work gone before a single line of feature code was rewritten.