feat(NearbyScreen): waypoint/navigate from list, TIME filter, addWaypoint helper

NearbyScreen:
- Hold Enter on a list row now shows Navigate and Save waypoint directly,
  without entering the detail view first
- TIME added as the last filter slot (LEFT/RIGHT cycles Fav→ALL→…→Snsr→TIME);
  time-sort shows age in right column and sorts by last-heard descending
- Save waypoint also available from detail view Options menu

UITask:
- Extract addWaypoint() helper (two overloads: with/without explicit timestamp)
  consolidating the full()+add()+saveWaypoints()+alert pattern; TrailScreen
  and QuickMsgScreen updated to use it

Fixes:
- SoundNotifier.h: correct NodePrefs.h include path (../NodePrefs.h)
- kbAddSensorPlaceholders: dereference _kb pointer in SettingsScreen,
  QuickMsgScreen and BotScreen (signature changed to KeyboardWidget&)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

examples/companion_radio/ui-new/UITask.cpp

@@ -1964,6 +1964,21 @@ void UITask::saveWaypoints() {
   f.close();
 }
 
+bool UITask::addWaypoint(int32_t lat, int32_t lon, uint32_t ts, const char* label) {
+  if (_waypoints.full()) { showAlert("Waypoints full", 1000); return false; }
+  if (_waypoints.add(lat, lon, ts, label)) {
+    saveWaypoints();
+    showAlert("Waypoint saved", 800);
+    return true;
+  }
+  showAlert("Waypoints full", 1000);
+  return false;
+}
+
+bool UITask::addWaypoint(int32_t lat, int32_t lon, const char* label) {
+  return addWaypoint(lat, lon, (uint32_t)rtc_clock.getCurrentTime(), label);
+}
+
 char UITask::checkDisplayOn(char c) {
   if (_display != NULL) {
     if (!_display->isOn()) {