Add a graph-based model to the comparison

[Tortar]

As discussed in #60

[Datseris]

Note that here we mean graph as a space. Such as agents moving from city to city, and each city is a node in a graph that may host many agents.

This is not the same as each agent being a node in a graph and having connections to other agents, which is done in frameworks likke Vanaha.jl.

[Tortar]

Available in Mesa-examples:

https://github.com/projectmesa/mesa-examples/tree/main/examples/virus_on_network
https://github.com/projectmesa/mesa-examples/tree/main/examples/boltzmann_wealth_model_network

[Datseris]

In this network implementation, agents must be located on a node, with a limit of one agent per node. In order to give or receive the unit of money, the agent must be directly connected to the other agent (there must be a direct link between the nodes).

This isn't a graph-as-space model. This model is suited more for #71 .

Similarly for the virus:

This model demonstrates the spread of a virus through a network. Although the model is somewhat abstract, one interpretation is that each node represents a computer, and we are modeling the progress of a computer virus (or worm) through this network.

[Tortar]

good catch, forgot about this