fix(mesh): first-class Reticulum — probe boot-race, live config apply, name propagation, daemon-death detection

Root causes found and fixed after live debugging on archi-dev-box (all
verified on real RNode hardware, archi-dev-box <-> archy-x250-dev E2E):

- probe_rnode raced the board's own boot: opening the port pulses DTR/RTS
  through USB-UART bridges (CP2102/Heltec V3), the ESP32 power-cycles and
  spends ~2.5-3s in boot ROM, and the KISS DETECT written 300ms after open
  landed in the void — so an RNode could NEVER connect on these boards.
  Now: immediate probe (fast path), then drain-until-quiet boot settle and
  a second DETECT with a fresh response window.
- MeshService::configure() only restarted the listener on enable/disable —
  device_kind/device_path/advert_name/RF-param changes were silent no-ops
  until a full process restart (the setup modal's apply/keep-as-is did
  nothing). Material config changes now bounce the listener; the open
  sequence races the shutdown signal so stop() no longer burns the full
  15s timeout mid-probe; mesh.configure applies in the background instead
  of stalling every status poll behind the service write-lock.
- The mesh name was write-only: config.advert_name had no reader,
  server.set-name never reached the mesh service, and Reticulum's
  set_advert_name was a no-op (daemon display name fixed at spawn, and the
  ARCHY:2 announce blob REPLACED the LXMF display name — every archy node
  was anonymous on RNS). Now: advert_name > server name precedence feeds
  the session, renames restart it live, the daemon gets --display-name at
  spawn plus a set_name RPC verb, and announces carry the LXMF-standard
  msgpack name with the identity blob appended as an extra list element
  stock clients (Sideband/NomadNet) ignore.
- Dead reticulum-daemon was invisible for up to 30min (RX-stall watchdog):
  child exit / RPC-EOF now fails try_recv_frame so the session reconnects.
- Setup modal re-trigger loop: plugged_at used the tty node's mtime, which
  bumps on every open — each probe invalidated the dismissal key. Use
  btime/ctime (only change on real plugs).
- ARCHY:2 identity adverts (re-emitted every 60s over Reticulum) stomped
  the federation twin's real name with a synthetic Archy-… placeholder and
  nulled its position; blob-only announces no longer assert a name, blob
  strings can never become display names, and stale blob names are healed
  at peers.json load.
- mesh.broadcast on Meshtastic sent heartbeat+time only (no identity);
  SendAdvert now also fires a want_response NodeInfo broadcast.
- New mesh.refresh RPC: actively re-queries the radio contact table (the
  UI Refresh button previously only re-read server caches).
- Reticulum peers now track last_advert (announce time) and mark existing
  peers reachable on inbound traffic.
- Boot auto-enable no longer force-enables mesh when an operator
  explicitly disabled it (only fires when no config file exists).

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

core/archipelago/src/api/rpc/system/handlers.rs

@@ -61,6 +61,28 @@ impl RpcHandler {
 
         info!("Server name updated to: {}", name);
 
+        // Propagate to the mesh: the listener advertises the server name (when
+        // no explicit mesh advert_name overrides it), but it was only read at
+        // process startup — a rename never reached the radio/RNS until the
+        // next full restart. Push it into the service and bounce the listener
+        // in the background (the restart re-probes the radio, which can take
+        // seconds — don't block the rename response on it).
+        {
+            let mesh_arc = self.mesh_service_arc();
+            let name_for_mesh = name.clone();
+            tokio::spawn(async move {
+                let mut guard = mesh_arc.write().await;
+                if let Some(svc) = guard.as_mut() {
+                    svc.set_server_name(Some(name_for_mesh));
+                    if svc.config().advert_name.is_none() {
+                        if let Err(e) = svc.restart_listener_if_running().await {
+                            warn!("Mesh listener restart after rename failed: {}", e);
+                        }
+                    }
+                }
+            });
+        }
+
         // Push the new name to federation peers in background
         let data_dir = self.config.data_dir.clone();
         let state_manager = self.state_manager.clone();