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.

Devices/lilygo-tlora-pager/Source/drivers/TloraPager.cpp

@@ -19,10 +19,10 @@ static int stop(Device* device) {
 Driver tlora_pager_driver = {
     .name = "T-Lora Pager",
     .compatible = (const char*[]) { "lilygo,tlora-pager", nullptr },
-    .startDevice = start,
-    .stopDevice = stop,
+    .start_device = start,
+    .stop_device = stop,
     .api = nullptr,
-    .deviceType = nullptr,
+    .device_type = nullptr,
     .owner = &device_module,
     .driver_private = nullptr
 };