Watch face selection at build time

Watch faces can now be selected at buid time. It's implemented in a similar way than the selection of user apps, using a list of watch face description that is generated at build time (consteval, constexpr)

src/displayapp/UserApps.h

@@ -7,7 +7,12 @@
 #include "displayapp/screens/Twos.h"
 #include "displayapp/screens/Tile.h"
 #include "displayapp/screens/ApplicationList.h"
-#include "displayapp/screens/Clock.h"
+#include "displayapp/screens/WatchFaceDigital.h"
+#include "displayapp/screens/WatchFaceAnalog.h"
+#include "displayapp/screens/WatchFaceCasioStyleG7710.h"
+#include "displayapp/screens/WatchFaceInfineat.h"
+#include "displayapp/screens/WatchFacePineTimeStyle.h"
+#include "displayapp/screens/WatchFaceTerminal.h"
 
 namespace Pinetime {
   namespace Applications {
@@ -21,16 +26,34 @@ namespace Pinetime {
       Screens::Screen* (*create)(AppControllers& controllers);
     };
 
+    struct WatchFaceDescription {
+      WatchFace watchFace;
+      const char* name;
+      Screens::Screen* (*create)(AppControllers& controllers);
+      bool (*isAvailable)(Controllers::FS& fileSystem);
+    };
+
     template <Apps t>
     consteval AppDescription CreateAppDescription() {
       return {AppTraits<t>::app, AppTraits<t>::icon, &AppTraits<t>::Create};
     }
 
+    template <WatchFace t>
+    consteval WatchFaceDescription CreateWatchFaceDescription() {
+      return {WatchFaceTraits<t>::watchFace, WatchFaceTraits<t>::name, &WatchFaceTraits<t>::Create, &WatchFaceTraits<t>::IsAvailable};
+    }
+
     template <template <Apps...> typename T, Apps... ts>
     consteval std::array<AppDescription, sizeof...(ts)> CreateAppDescriptions(T<ts...>) {
       return {CreateAppDescription<ts>()...};
     }
 
+    template <template <WatchFace...> typename T, WatchFace... ts>
+    consteval std::array<WatchFaceDescription, sizeof...(ts)> CreateWatchFaceDescriptions(T<ts...>) {
+      return {CreateWatchFaceDescription<ts>()...};
+    }
+
     constexpr auto userApps = CreateAppDescriptions(UserAppTypes {});
+    constexpr auto userWatchFaces = CreateWatchFaceDescriptions(UserWatchFaceTypes {});
   }
 }