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.

Drivers/EspLcdCompat/Source/EspLcdDisplay.cpp

@@ -10,9 +10,10 @@
 static const auto LOGGER = tt::Logger("EspLcdDisplay");
 
 EspLcdDisplay::~EspLcdDisplay() {
-    if (displayDriver != nullptr && displayDriver.use_count() > 1) {
-        tt_crash("DisplayDriver is still in use. This will cause memory access violations.");
-    }
+    check(
+        displayDriver == nullptr || displayDriver.use_count() < 2, // 1 reference is held by this class
+        "DisplayDriver is still in use. This will cause memory access violations."
+    );
 }
 
 bool EspLcdDisplay::start() {
@@ -115,7 +116,7 @@ std::shared_ptr<tt::hal::display::DisplayDriver> EspLcdDisplay::getDisplayDriver
         } else if (lvgl_port_config.color_format == LV_COLOR_FORMAT_RGB888) {
             color_format = tt::hal::display::ColorFormat::RGB888;
         } else {
-            tt_crash("unsupported driver");
+            check(false, "unsupported driver");
         }
 
         displayDriver = std::make_shared<EspLcdDisplayDriver>(