DiscoveryHost

What discovery reads of the app it runs in (work-placement §WPK-4 item 5, §WPI-11).

Declared in src/libs/libpair/discovery/DiscoveryHost.hpp.

Detailed description

`DiscoveryClient` and `LANDiscovery` took a `Node` until §WPI-11, and read eight things from it. This struct gives those eight things and nothing else, so the pairing feature makes discovery without a `Node`. The member functions have the names of the `Node` accessors that they replace.

The key store, the associate and the settings are functions, because they change: an identity switch gives the node another key store and another associate. The other members do not change for the life of the app.

A host with no key store source is null. Discovery that has a null host sends nothing, as it did with a null node.