Add a new flag to P2P.list_nodes()

### Is your feature request related to a problem?

Network transactions are stored on all nodes. So when validating a transaction, the validations nodes ping all the node to determine the replication tree.
But it is possible that some nodes are completely unavailable as described by issue #1323. It is not necessary to ping these nodes

### Describe the solution you'd like

`P2P.list_nodes()` and `P2P.authorized_nodes` could have a new option flag to filter the nodes that are completely unavailable.

### Additional context

It will need to add a new field to the Node struct and modifying the p2p mem table

### Epic

_No response_

Start by reading issue #1323 and tracing P2P.list_nodes(), P2P.authorized_nodes, the Node struct, and the p2p mem table. Determine how completely unavailable nodes are represented, then make the new option filter them from both node-listing paths. Done means the flag is supported and unavailable nodes are excluded when requested without changing the default behavior.

Written by the indexing model from the issue text.