SD card improvements (#214)

- Implement SD card locking logic and helper functions
- Fix issue with running ELF apps from SD card: this would crash when launched from the AppList
- Reduce Boot app wait time to 1 second
- Speed up boot by about 0.1 second by moving app&service registration to the Boot app
- Files app now uses proper SD card mount point name (and multiple SD cards)
- Removed `TT_SCREENSHOT_MODE`

Tactility/Source/app/boot/Boot.cpp

@@ -5,7 +5,7 @@
 #include "Tactility/service/loader/Loader.h"
 #include "Tactility/lvgl/Style.h"
 
-#include <Tactility/Tactility.h>
+#include <Tactility/TactilityPrivate.h>
 #include <Tactility/hal/Display.h>
 #include <Tactility/hal/usb/Usb.h>
 #include <Tactility/kernel/SystemEvents.h>
@@ -51,10 +51,13 @@ private:
             hal::usb::resetUsbBootMode();
             hal::usb::startMassStorageWithSdmmc();
         } else {
+            initFromBootApp();
+
             TickType_t end_time = tt::kernel::getTicks();
             TickType_t ticks_passed = end_time - start_time;
             TickType_t minimum_ticks = (CONFIG_TT_SPLASH_DURATION / portTICK_PERIOD_MS);
             if (minimum_ticks > ticks_passed) {
+                TT_LOG_I(TAG, "Remaining delay: %lu", minimum_ticks - ticks_passed);
                 kernel::delayTicks(minimum_ticks - ticks_passed);
             }