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.

TactilityKernel/Source/device.cpp

@@ -264,7 +264,7 @@ void for_each_device_of_type(const DeviceType* type, void* callbackContext, bool
     for (auto* device : ledger.devices) {
         auto* driver = device->internal.driver;
         if (driver != nullptr) {
-            if (driver->deviceType == type) {
+            if (driver->device_type == type) {
                 if (!on_device(device, callbackContext)) {
                     break;
                 }

TactilityKernel/Source/driver.cpp

@@ -159,8 +159,8 @@ error_t driver_bind(Driver* driver, Device* device) {
         goto error;
     }
 
-    if (driver->startDevice != nullptr) {
-        error = driver->startDevice(device);
+    if (driver->start_device != nullptr) {
+        error = driver->start_device(device);
         if (error != ERROR_NONE) {
             goto error;
         }
@@ -187,8 +187,8 @@ error_t driver_unbind(Driver* driver, Device* device) {
         goto error;
     }
 
-    if (driver->stopDevice != nullptr) {
-        error = driver->stopDevice(device);
+    if (driver->stop_device != nullptr) {
+        error = driver->stop_device(device);
         if (error != ERROR_NONE) {
             goto error;
         }

TactilityKernel/Source/drivers/root.cpp

@@ -8,10 +8,10 @@ extern "C" {
 Driver root_driver = {
     .name = "root",
     .compatible = (const char*[]) { "root", nullptr },
-    .startDevice = nullptr,
-    .stopDevice = nullptr,
+    .start_device = nullptr,
+    .stop_device = nullptr,
     .api = nullptr,
-    .deviceType = nullptr,
+    .device_type = nullptr,
     .owner = nullptr,
     .driver_private = nullptr
 };