Refactor LVGL code into kernel module (#472)

* **New Features**
  * Added a standalone LVGL module and enabled LVGL support in the simulator for richer local UI testing.

* **Refactor**
  * HAL and LVGL split into distinct modules; startup and device attach/detach flows reorganized for clearer lifecycle management.
  * Public APIs tightened with clearer nullability/documentation.

* **Bug Fixes**
  * More consistent LVGL start/stop and device attach/detach behavior for improved stability.

Tactility/Private/Tactility/app/AppInstance.h

@@ -36,7 +36,7 @@ class AppInstance : public AppContext {
      * When these are stored in the app struct, the struct takes ownership.
      * Do not mutate after app creation.
      */
-    std::shared_ptr<const Bundle> _Nullable parameters;
+    std::shared_ptr<const Bundle> parameters;
 
     std::shared_ptr<App> app;
 

Tactility/Private/Tactility/lvgl/EspLvglPort.h

@@ -1,11 +0,0 @@
-#pragma once
-
-#ifdef ESP_PLATFORM
-
-namespace tt::lvgl {
-
-bool initEspLvglPort();
-
-}
-
-#endif

Tactility/Private/Tactility/lvgl/LvglPrivate.h

@@ -1,9 +1,11 @@
 #pragma once
 
-#include <Tactility/hal/Configuration.h>
+#include <Tactility/lvgl/Lvgl.h>
 
 namespace tt::lvgl {
 
-void init(const hal::Configuration& config);
+void attachDevices();
 
-} // namespace
+void detachDevices();
+
+}

Tactility/Private/Tactility/service/gui/GuiService.h

@@ -39,7 +39,7 @@ class GuiService final : public Service {
     // App-specific
     std::shared_ptr<app::AppInstance> appToRender = nullptr;
 
-    lv_obj_t* _Nullable keyboard = nullptr;
+    lv_obj_t* keyboard = nullptr;
     lv_group_t* keyboardGroup = nullptr;
 
     bool isStarted = false;

Tactility/Private/Tactility/service/screenshot/Screenshot.h

@@ -48,7 +48,7 @@ public:
     void stop();
 };
 
-std::shared_ptr<ScreenshotService> _Nullable optScreenshotService();
+std::shared_ptr<ScreenshotService> optScreenshotService();
 
 } // namespace