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/mbr_gpt.h

@@ -81,4 +81,10 @@ typedef struct _gpt_t
 	gpt_entry_t  entries[128];
 } gpt_t;
 
+bool mbr_has_gpt(const mbr_t *mbr);
+void wctombs(const u16 *src, char *dest, u32 len_max);
+void ctowcs(const char *src, u16 *dest, u32 len_max);
+s32 gpt_get_part_by_name(gpt_t *gpt, const char* name, s32 prev);
+
+
 #endif