feat(route): trace per link, to the node or the last repeater, find where it stops; channel order re-sorts on entry

Core: PathEditor results are links (node k hearing k-1 and back); toNode()
off traces only the repeaters (a companion answers only with repeat on);
probe() traces to each repeater in turn after no reply; failures carry a
reason; an empty list saves "direct". PingEngine takes over a slot left past
its timeout. A kept route: the dropped heard path isn't announced to the app
nor bumps lastmod; an app update keeps the flag only if it leaves the route.
Marker boxes sized for every dot and name (overflow).

ui-lvgl Route: one line per node with out / back dB coloured by quality, tap
a hop to move / remove, tap the node to include it, Keep in the header, Find
where beside a no-reply status. ui-new Path: To node / Find break rows,
result alerts, cursor kept on its action.

Channels: ui-new re-sorts the list on entering it, cursor on the same channel.
Docs: Path and trace, Channel order. Sim hooks: open route, add channel,
open messages.

Checked in the browser sim (L2 + ui-new peer + repeater); not on hardware.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

examples/companion_radio/ui-new/UITask.h

@@ -329,6 +329,8 @@ public:
   void gotoBotScreen();
   void pickAdminTarget();                  // Admin is remote-only: open Nodes to pick a repeater/room
   void openAdminFor(const ContactInfo& ci, bool from_picker); // canonical Admin entry for a specific target (Nodes' Hold-Enter menu or the picker above)
+  void openRouteFor(const uint8_t* pub_key);   // Nodes > a contact > Path / trace (sim harness)
+  void openMessagesList() { gotoMessagesScreen(); }   // sim harness
   void gotoNearbyScreen();
   void gotoDashboardConfig();
   void gotoAutoAdvertScreen();