Add support for generating snapshot for given network

[michalkucharczyk]

Is your feature request related to a problem? Please describe.

Would be nice to have support for snapshot generation directly in zombienet-sdk.
E.g. node.get_snapshot() which can later be used for starting from snapshot.

I will provide more details about API soon.

Describe the solution you'd like

I will provide more details about API soon.

Describe alternatives you've considered

No response

Additional context

No response

[michalkucharczyk]

@pepoviola some proposal here:
#542

Let's discuss there if shape is OK.