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/app/wificonnect/View.cpp

@@ -21,7 +21,7 @@ void View::resetErrors() {
     lv_obj_add_flag(connection_error, LV_OBJ_FLAG_HIDDEN);
 }
 
-static void onConnect(TT_UNUSED lv_event_t* event) {
+static void onConnect(lv_event_t* event) {
     auto wifi = std::static_pointer_cast<WifiConnect>(getCurrentApp());
     auto& view = wifi->getView();