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>

docs/solo/messages.md

@@ -124,6 +124,10 @@ correctly whatever the keyboard is set to.
 | Pin to dial | Puts it on the Favourites page |
 | Edit, Delete | Renames it or changes its secret; removes it |
 
+The order of the list is in Settings › Contacts › **Channel order**: as the
+channels were added (Slots), the one with the newest message first (Newest),
+or by name. Favourites stay on top while **Favourites first** is on.
+
 **+ Add channel** at the end of the list adds:
 
 - **Public**: the default public channel, if you deleted it.