Implement UI scaling and more (#501)

**New Features**
 * Runtime font accessors and new symbol fonts for text, launcher, statusbar, and shared icons.
 * Added font height base setting to device.properties
 * Text fonts now have 3 sizes: small, default, large

**Improvements**
 * Renamed `UiScale` to `UiDensity`
 * Statusbar, toolbar and many UI components now compute heights and spacing from fonts/density.
 * SSD1306 initialization sequence refined for more stable startup.
 * Multiple image assets replaced by symbol-font rendering.
 * Many layout improvements related to density, font scaling and icon scaling
 * Updated folder name capitalization for newer style

Tactility/Source/service/memorychecker/MemoryCheckerService.cpp

@@ -1,12 +1,11 @@
-#include <Tactility/Tactility.h>
-
 #include <Tactility/Logger.h>
 #include <Tactility/lvgl/Statusbar.h>
 #include <Tactility/service/ServiceContext.h>
 #include <Tactility/service/ServiceManifest.h>
-#include <Tactility/service/ServicePaths.h>
 #include <Tactility/service/memorychecker/MemoryCheckerService.h>
 
+#include <tactility/lvgl_symbols_statusbar.h>
+
 namespace tt::service::memorychecker {
 
 static const auto LOGGER = Logger("MemoryChecker");
@@ -55,8 +54,7 @@ bool MemoryCheckerService::onStart(ServiceContext& service) {
     auto lock = mutex.asScopedLock();
     lock.lock();
 
-    auto icon_path = std::string("A:") + service.getPaths()->getAssetsPath("memory_alert.png");
-    statusbarIconId = lvgl::statusbar_icon_add(icon_path, false);
+    statusbarIconId = lvgl::statusbar_icon_add(LVGL_SYMBOL_MEMORY, false);
     lvgl::statusbar_icon_set_visibility(statusbarIconId, false);
 
     timer.setCallbackPriority(Thread::Priority::Lower);