perf(client): code-split every heavy route via React.lazy()
Cuts the initial bundle roughly in half. Users who open Home,
Extensions, or FAQ download ~343 kB / 106 kB gz instead of 817 kB /
230 kB gz. Heavy clinical reference data (PE_DATA, Fenton LMS,
Rosner BP splines, 15 Bedside drug panels, 10 Calculator formulas,
13 Settings sub-sections, 10 Admin sub-tabs) only loads when the
user opens that route.
client/src/App.tsx
Every route except Home / Extensions / FAQ wrapped in
React.lazy(() => import(...)) + <Suspense fallback>. Extensions and
FAQ stay in the main chunk because they're small (3 kB, 2 kB) and
likely visited early. The RouteFallback component shows a single
"Loading…" line — Vite prefetches chunks on hover so the delay is
typically invisible.
Resulting chunks (gzipped):
• index.js 106 kB React + Router + Query + Layout +
Home + Extensions + FAQ
• Bedside.js 33 kB 15 clinical dosing panels
• PeGuide.js 36 kB PE_DATA hierarchy + scales + sounds
• Calculators.js 42 kB All 10 calculators + BP Rosner
coefficients + Fenton + BMI LMS
• Settings.js 10 kB 13 Settings sub-sections
• Admin.js 7 kB 10 Admin sub-tabs
• Learning.js 3 kB
• Fenton chunk (shared) 3 kB Reused between Bedside neonatal
and the Growth Charts calculator
• Note pages (each) 1-2 kB Encounter / SOAP / Well / Sick /
Hospital / Chart / Dictation / Vax /
Catch-up individually chunked
Vite's 500 kB chunk-size warning is gone. No functional changes.