fix(router): derive basename from <base href>, not hardcoded /krishna_sales

The mount path is set per-placement by the frontgen server's <base href>
(/krishna-sales/ on qa). The hardcoded /krishna_sales basename didn't match,
so the Router refused to render. Read it from the document base so one
artifact serves any mount path.

src/App.tsx

@@ -14,10 +14,16 @@ function RootRedirect() {
 
 import { routeConfig } from './routesConfig'
 
+// Mount path comes from the document <base href> the frontgen server writes at
+// placement time (e.g. "/krishna-sales/"), so one built artifact serves any
+// mount without a hardcoded slug. Falls back to "/" for local dev.
+const routerBasename =
+  (document.querySelector('base')?.getAttribute('href') || '/').replace(/\/$/, '') || '/'
+
 function App() {
   return (
     <AuthProvider>
-      <BrowserRouter basename="/krishna_sales">
+      <BrowserRouter basename={routerBasename}>
         <Routes>
           <Route path="/login" element={<LoginPage />} />
           <Route element={<ConsoleLayout />}>