feat: a node map and a calendar on ui-new, a banner switch on the L2

- Nearby › Map (ui-new): the positioned nodes and you on one view, scaled
  to fit, with north, a scale bar and the selected node's name and
  distance; Left / Right picks a node, Up / Down zooms on it, Enter opens it.
- Clock tools › Calendar (ui-new): the month with today and the alarm's
  days; a tight grid on small screens, Left / Right pages the months.
- L2 Settings: a Message banner switch (on / off) in place of ui-new's
  three-way alert setting.
- Simulator: sim_nodes() puts eight positioned contacts around Kraków.

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

examples/companion_radio/ui-new/UITask.h

@@ -288,6 +288,7 @@ public:
   void simMessage(const char* text);   // sim tests: a channel message arrives
   void simUnread(int which);           // sim tests: read and new messages, opened
   void simDisplay(bool on);            // sim tests: the display off / on
+  void simNodes();                     // sim tests: you and nodes with positions, Nodes open
 #endif
   void openContactDM(const ContactInfo& ci);
   void openChannelHistory(uint8_t channel_idx);   // Favourites dial: open a pinned channel