add links messages

Introduce two new wire messages, LINKS and LINKS_REPLY (swarm::links).
A member answers with its links: for each peer, the transport, whether
it’s relayed, the RTT, and whether it’s dormant.  It answers members
only, at most every 5 s.  This bumps wire::VERSION to 7.  Every build
answers, with or without the feature, so every node needs this patch
before the map shows anything beyond its own node.

1 files changed, 2 insertions, 0 deletions

diff --git a/src/state/mod.rs b/src/state/mod.rs
index fec164d..d7c80c2 100644
--- a/src/state/mod.rs
+++ b/src/state/mod.rs
@@ -112,6 +112,8 @@ pub(crate) struct AppState {
     pub(crate) electorate_window: Duration,
     /// Chunked transfers served and fetched (`swarm::blob`).
     pub(crate) blobs: Arc<crate::swarm::blob::Blobs>,
+    /// LINKS asked and answered, for a map of the swarm (`swarm::links`).
+    pub(crate) links: Arc<crate::swarm::links::Links>,
     /// HTTP API users who may write protocol data through the store API
     /// (`--protocol-writers`).
     pub(crate) protocol_writers: Arc<std::collections::HashSet<String>>,