Enhance command statistical analysis

### Search before asking

- [x] I had searched in the [issues](https://github.com/apache/kvrocks/issues) and found no similar issues.

### Motivation

For the command execution analysis module, add namespace isolation to distinguish the execution status of each namespace

### Solution



### Are you willing to submit a PR?

- [ ] I'm willing to submit a PR!

Start by locating the command execution analysis module and examining how execution status is currently collected. Define how namespace isolation should distinguish each namespace's status, using the attached solution images as context; the work is done when analysis results are separated by namespace and the relevant behavior is covered by tests.

Written by the indexing model from the issue text.