Add full shell, replaceable Omics adapter and bilingual interaction

Implement approved specification #32 and tickets #33-#37. Keep host authentication server-verified and pin session interaction language. Compile scoped base selectors for browser compatibility and retain full gutters during CSS pruning.

frontend/src/App.tsx

@@ -1,11 +1,12 @@
 import { QueryClientProvider } from "@tanstack/react-query";
 import { queryClient } from "./app/queryClient";
 import { AuthGate } from "./auth/AuthGate";
+import { ShellProvider } from "./shell/host/ShellProvider";
 
 export function App() {
   return (
     <QueryClientProvider client={queryClient}>
-      <AuthGate />
+      <ShellProvider><AuthGate /></ShellProvider>
     </QueryClientProvider>
   );
 }