Add web client and containerized deployment stack

Web client:

- Added React + TypeScript + Vite + Tailwind application in web/.

- Implemented auth, chat list, chat messages, typing indicators, file uploads, and voice recording/playback.

- Added typed API layer, Zustand stores, and realtime websocket hook integration.

Containerization:

- Added backend Dockerfile and project .dockerignore.

- Added web multi-stage Dockerfile with nginx static hosting and API/WS reverse proxy.

- Added full docker-compose stack with postgres, redis, minio, backend, worker, mailpit, and web.

- Added MinIO bucket bootstrap init job and updated README with Docker quick-start.

web/src/app/App.tsx

@@ -0,0 +1,31 @@
+import { useEffect } from "react";
+import { AuthPage } from "../pages/AuthPage";
+import { ChatsPage } from "../pages/ChatsPage";
+import { useAuthStore } from "../store/authStore";
+
+export function App() {
+  const accessToken = useAuthStore((s) => s.accessToken);
+  const me = useAuthStore((s) => s.me);
+  const loadMe = useAuthStore((s) => s.loadMe);
+  const refresh = useAuthStore((s) => s.refresh);
+  const logout = useAuthStore((s) => s.logout);
+
+  useEffect(() => {
+    if (!accessToken) {
+      return;
+    }
+    loadMe().catch(async () => {
+      try {
+        await refresh();
+        await loadMe();
+      } catch {
+        logout();
+      }
+    });
+  }, [accessToken, loadMe, refresh, logout]);
+
+  if (!accessToken || !me) {
+    return <AuthPage />;
+  }
+  return <ChatsPage />;
+}