Simplify app registration with TactilityCpp (#7)

- Simplified app registration with a C++ wrapper for the TactilityC.
- Rename the various app classes from `Application` to more specific names like `Calculator` etc.

Apps/Calculator/main/Source/Calculator.h

@@ -5,8 +5,9 @@
 #include <lvgl.h>
 #include <deque>
 #include <Str.h>
+#include <TactilityCpp/App.h>
 
-class Calculator {
+class Calculator final : public App {
 
     lv_obj_t* displayLabel;
     lv_obj_t* resultLabel;
@@ -23,5 +24,5 @@ class Calculator {
 
 public:
 
-    void onShow(AppHandle context, lv_obj_t* parent);
+    void onShow(AppHandle context, lv_obj_t* parent) override;
 };

Apps/Calculator/main/Source/main.cpp

@@ -1,26 +1,10 @@
-#include <tt_app.h>
 #include "Calculator.h"
-
-static void onShowApp(AppHandle appHandle, void* data, lv_obj_t* parent) {
-    static_cast<Calculator*>(data)->onShow(appHandle, parent);
-}
-
-static void* createAppData() {
-    return new Calculator();
-}
-
-static void destroyAppData(void* app) {
-    delete static_cast<Calculator*>(app);
-}
+#include <TactilityCpp/App.h>
 
 extern "C" {
 
 int main(int argc, char* argv[]) {
-    tt_app_register((AppRegistration) {
-        .createData = createAppData,
-        .destroyData = destroyAppData,
-        .onShow = onShowApp,
-    });
+    registerApp<Calculator>();
     return 0;
 }