## Summary
- Closes#24
- Introduce `AppRouter` + `getAppRouter()` so Capacitor uses `HashRouter` (filesystem bundle, no nginx rewrite) while web keeps `BrowserRouter`
- Isolate platform checks in `nativePlatform` (no `Capacitor.isNativePlatform()` sprinkled through the route tree)
- Auth forced redirects (`axiosApi` → `/signin/`) use hash-safe `redirectToAppPath` on native
- Leave CRA `homepage` / absolute `PUBLIC_URL` asset paths unchanged so `/var/www/{env}.chat.aimloperations/html` deploy stays intact; HashRouter keeps document URL at the bundle root so assets resolve
## Test plan
- [x] Unit tests: `AppRouter` + `nativePlatform` (`npm run test:ci`)
- [ ] Capacitor build: open nested route (`/#/account/`), force WebView reload — no blank/404
- [ ] Browser back/forward + Android hardware back with HashRouter
- [ ] Web deploy smoke: deep link reload at `/account/` still works via nginx rewrite
- [ ] Confirm login redirects after 401 still land on sign-in (web path + native hash)Reviewed-on: #27