Is your improvement request related to a feature? Please describe (👍 if you like this request)

Now the SPDK JSON client is not thread-safe, while the SPDK engine service cannot use a lock to protect it. This leads to some unexpected errors.

Describe the solution you'd like

Make the client thread-safe:

• Launch a response channel for each call
• Rely on SPDK request ID to forward the responses to the correct channel the callers are waiting on.

Describe alternatives you've considered

N/A

Additional context

Without this, some features like offline rebuilding are unstable.