Feature: Add nanocl stats command to support multiple process monitoring

[leon3s]

Is your feature request related to a problem? Please describe.
Currently, there is no nanocl stats command available, making it difficult for developers to monitor resource usage (e.g., CPU, memory) of processes managed by Nanocl. This can be a significant gap for those who need real-time insight into the performance and resource consumption of multiple processes.

Describe the solution you'd like
Implement a nanocl stats command that can display real-time resource usage for specified processes. This command should accept multiple process names as arguments, allowing usage such as nanocl stats my-process my-second-process, with combined resource statistics output for all specified processes.

Describe alternatives you've considered

• Using external monitoring tools that may not be tightly integrated with Nanocl, adding setup complexity.
• Manually checking resource consumption per process using system tools like top or htop, which lacks process-specific integration within Nanocl.

Additional context
Adding a nanocl stats command would greatly enhance the ability to monitor and manage the performance of services within the Nanocl ecosystem. This feature would provide a streamlined way for developers to get real-time metrics on multiple processes, supporting better optimization and troubleshooting efforts.