Various improvements (#461)

* **New Features**
  * Time and delay utilities added (ticks, ms, µs); SD card now uses an expansion-header CS pin; HTTP downloads warn when run on the GUI task and yield to avoid blocking.

* **Bug Fixes / Reliability**
  * Many hard-crash paths converted to guarded checks to reduce abrupt termination and improve stability.

* **Tests**
  * Unit tests added to validate time and delay accuracy.

* **Chores**
  * License header and build/macro updates.

Tactility/Source/lvgl/Toolbar.cpp

@@ -2,6 +2,7 @@
 
 #include <Tactility/lvgl/Toolbar.h>
 
+#include <Tactility/Check.h>
 #include <Tactility/service/loader/Loader.h>
 #include <Tactility/lvgl/Spinner.h>
 
@@ -63,7 +64,7 @@ static const lv_obj_class_t toolbar_class = {
     .theme_inheritable = false
 };
 
-static void stop_app(TT_UNUSED lv_event_t* event) {
+static void stop_app(lv_event_t* event) {
     app::stop();
 }
 
@@ -166,7 +167,7 @@ void toolbar_set_nav_action(lv_obj_t* obj, const char* icon, lv_event_cb_t callb
 
 lv_obj_t* toolbar_add_button_action(lv_obj_t* obj, const char* imageOrButton, bool isImage, lv_event_cb_t callback, void* user_data) {
     auto* toolbar = reinterpret_cast<Toolbar*>(obj);
-    tt_check(toolbar->action_count < TOOLBAR_ACTION_LIMIT, "max actions reached");
+    check(toolbar->action_count < TOOLBAR_ACTION_LIMIT, "max actions reached");
     toolbar->action_count++;
 
     auto ui_scale = hal::getConfiguration()->uiScale;