devfront 로그인 페이지 auto redirect SSO 진입 추가

devfront/src/features/auth/AuthCallbackPage.tsx

@@ -17,12 +17,19 @@ export default function AuthCallbackPage() {
     }
 
     if (auth.isAuthenticated) {
-      navigate("/", { replace: true });
+      const returnTo =
+        typeof auth.user?.state === "object" &&
+        auth.user?.state !== null &&
+        "returnTo" in auth.user.state &&
+        typeof auth.user.state.returnTo === "string"
+          ? auth.user.state.returnTo
+          : "/clients";
+      navigate(returnTo, { replace: true });
     } else if (auth.error) {
       console.error("Auth Error:", auth.error);
       navigate("/login", { replace: true });
     }
-  }, [auth.isAuthenticated, auth.error, navigate]);
+  }, [auth.isAuthenticated, auth.error, navigate, auth.user?.state]);
 
   return <div>Loading Auth...</div>;
 }