feat(mocker): add multi-worker replay and router startup fixes (#7553)

Signed-off-by: PeaBrane <yanrpei@gmail.com>

lib/mocker/src/replay/online/mod.rs

+// SPDX-FileCopyrightText: Copyright (c) 2025-2026 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
+// SPDX-License-Identifier: Apache-2.0
+
+mod runtime;
+
+pub(crate) use runtime::{simulate_concurrency_requests, simulate_trace_requests};