Initial commit: backend scaffold, auth, frontend login

- FastAPI + SQLAlchemy async + Alembic + Postgres backend
- Auth: JWT access + rotating refresh tokens, argon2, roles, audit log
- React 19 + Vite frontend: login page, protected route, auth context
- Docker Compose: postgres, redis, migrate, api, worker (placeholder), frontend/nginx

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

frontend/src/features/auth/ProtectedRoute.tsx

@@ -0,0 +1,23 @@
+import { Navigate, Outlet, useLocation } from 'react-router-dom'
+
+import { useAuth } from '@/features/auth/useAuth'
+
+/** Пропускает дальше только аутентифицированных; остальных отправляет на /login. */
+export function ProtectedRoute() {
+  const { status } = useAuth()
+  const location = useLocation()
+
+  if (status === 'loading') {
+    return (
+      <div className="page-center">
+        <span className="spinner" aria-label="Загрузка" />
+      </div>
+    )
+  }
+
+  if (status === 'unauthenticated') {
+    return <Navigate to="/login" state={{ from: location }} replace />
+  }
+
+  return <Outlet />
+}