Single-bundle build was tripping vite's 500 kB warning per chunk and
forcing every user to re-download the entire app on every deploy.
Manual chunks split the bundle along natural library boundaries so:
- Rarely-changing vendor libs (react-dom, react-router, lucide-react,
asciinema-player) cache across deploys.
- App code lives in its own `index-*.js` that's the only chunk that
changes when we ship feature work.
Split shape (manualChunks fn in vite.config.ts):
- charts — recharts + d3-*
- player — asciinema-player
- icons — lucide-react
- router — react-router / react-router-dom
- react-dom, react
- vendor — everything else in node_modules
Resulting bundle sizes (gzip):
index (app): 246 kB (gz 63)
react-dom: 182 kB (gz 57)
player: 176 kB (gz 65)
router: 42 kB (gz 15)
vendor: 36 kB (gz 14)
icons: 29 kB (gz 10)
Every chunk under the 600 kB ceiling we now set explicitly. The old
~705 kB single-chunk deploy is gone. No code changes — config only.
