M0 step 7: Settings, About, Storage, first-boot setup

- lib/apps_model (host-tested): SettingsMenu (rows, readable values,
  choices, validation messages) and SetupWizard (names, Region
  confirmation, timezone; saves only when finished)
- AppManager: modal Apps that Home/Back can't leave (setup wizard)
- SettingsApp: all settings plus Storage (usage, erase SD behind a
  dialog) and About (version, node id, battery, memory, uptime) pages,
  replacing the temporary Diagnostics App
- SetupApp: first-boot wizard, opened modally until SetupDone
- Node id and default names derived from the MAC like Meshtastic
- Widget demo is now hidden (About, then w)
- lib_ldf_mode = deep+ so libraries see each other's headers

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01EhqxQ49eCju4CzKYNjZzwT

src/ui/widgets.h

@@ -36,8 +36,9 @@ MeasureText bodyMeasure(Canvas& canvas);
 
 void statusBar(Canvas& c, const StatusInfo& info);
 
-// A selectable list; `label(i)` gives row i's text.
-void list(Canvas& c, const ListModel& model, theme::Rect area, const std::function<std::string(int)>& label);
+// A selectable list; `label(i)` gives row i's text and `value(i)`, if given, a right-aligned value.
+void list(Canvas& c, const ListModel& model, theme::Rect area, const std::function<std::string(int)>& label,
+          const std::function<std::string(int)>& value = nullptr);
 
 // Pre-wrapped lines starting at `firstLine`, with a scroll indicator when they don't all fit.
 void textLines(Canvas& c, const std::vector<std::string>& lines, int firstLine, theme::Rect area);