RefreshTokenResponse

{
    "success": true,
    "data": {
        "message": "Token refreshed successfully",
        "tokens": {
            "access_token": "eyJhbGciOiJIUzI1NiJ9...",
            "refresh_token": "a1b2c3d4e5f6...",
            "expires_in": 900,
            "token_type": "Bearer"
        }
    }
}