Nyx: emuMMC Manage window, Tools UI, and misc updates

- Add gui_emu_tools: emuMMC Manage window with correct positioning (LV_PROTECT_PARENT + re-parent to win)
- Tools: single SD button (tap = SD partition manager, 3s hold = eMMC)
- Remove emuSD from Nyx UI (tabs, UMS, partition manager); keep bootloader emusd
- Shorten Create emuMMC description text by one character
- Storage/build/config and dependency updates

Co-authored-by: Cursor <cursoragent@cursor.com>

bdk/storage/boot_storage.h

@@ -0,0 +1,24 @@
+#ifndef _BOOT_STORAGE_H
+#define _BOOT_STORAGE_H
+
+#include <libs/fatfs/ff.h>
+#include <utils/types.h>
+
+// check if boot1 (1mb), boot1, gpp, sd (in that order) have fat32 partition,
+// mount the partition and set the current drive to it
+bool boot_storage_mount();
+
+void boot_storage_unmount();
+void boot_storage_end();
+
+bool boot_storage_get_mounted();
+bool boot_storage_get_initialized();
+
+void *boot_storage_file_read(const char *path, u32 *fsize);
+int boot_storage_save_to_file(const void *buf, u32 size, const char *filename);
+
+FATFS *boot_storage_get_fs();
+
+u8 boot_storage_get_drive();
+
+#endif