fix: FTP storage backend, SD info display, time label alignment

- Fix FTP using FFAT instead of SD_MMC: define both NETWORK_TYPE (6) and
  STORAGE_TYPE (10) with numeric values to bypass FtpServerKey.h guard
- Fix SD capacity showing 'f/f GB': use integer math instead of floats
  (LVGL builtin sprintf lacks %f support)
- Fix time/date labels tilting 45°: set fixed width + LV_TEXT_ALIGN_CENTER
- Switch LVGL sprintf to C stdlib for future float compatibility

platformio.ini

@@ -36,8 +36,11 @@ build_flags =
     -Wl,--wrap=esp_ota_mark_app_valid_cancel_rollback
     ; Enable LVGL simple include
     -DLV_CONF_INCLUDE_SIMPLE
-    ; FTP server storage type: SD_MMC
+    ; FTP server: must define BOTH network + storage with numeric values
-    -DDEFAULT_STORAGE_TYPE_ESP32=STORAGE_SD_MMC
+    ; to prevent FtpServerKey.h from defaulting to FFAT
+    ; NETWORK_ESP32=6, STORAGE_SD_MMC=10
+    -DDEFAULT_FTP_SERVER_NETWORK_TYPE_ESP32=6
+    -DDEFAULT_STORAGE_TYPE_ESP32=10
     ; Suppress deprecation warnings
     -Wno-deprecated-declarations
     ; Allow #warning without failing build

src/lv_conf.h

@@ -16,7 +16,7 @@
  *=========================*/
 #define LV_USE_STDLIB_MALLOC    LV_STDLIB_BUILTIN
 #define LV_USE_STDLIB_STRING    LV_STDLIB_BUILTIN
-#define LV_USE_STDLIB_SPRINTF   LV_STDLIB_BUILTIN
+#define LV_USE_STDLIB_SPRINTF   LV_STDLIB_CLIB
 
 #define LV_MEM_SIZE (48U * 1024U)
 

src/ui.cpp

@@ -187,11 +187,21 @@ void ui_init()
     /* ────────────────────────────────────────────────────────────── */
     /*  CLOCK AREA  (y = 385 … 490)                                  */
     /* ────────────────────────────────────────────────────────────── */
-    lbl_time = make_label(scr, &lv_font_montserrat_40, CLR_WHITE,
+    lbl_time = lv_label_create(scr);
-                          LV_ALIGN_TOP_MID, 0, 398, "--:--");
+    lv_label_set_text(lbl_time, "--:--:--");
+    lv_obj_set_style_text_font(lbl_time, &lv_font_montserrat_40, 0);
+    lv_obj_set_style_text_color(lbl_time, lv_color_hex(CLR_WHITE), 0);
+    lv_obj_set_width(lbl_time, SCR_W);
+    lv_obj_set_style_text_align(lbl_time, LV_TEXT_ALIGN_CENTER, 0);
+    lv_obj_align(lbl_time, LV_ALIGN_TOP_MID, 0, 398);
 
-    lbl_date = make_label(scr, &lv_font_montserrat_18, CLR_GRAY,
+    lbl_date = lv_label_create(scr);
-                          LV_ALIGN_TOP_MID, 0, 456, "--- --, ----");
+    lv_label_set_text(lbl_date, "--- --, ----");
+    lv_obj_set_style_text_font(lbl_date, &lv_font_montserrat_18, 0);
+    lv_obj_set_style_text_color(lbl_date, lv_color_hex(CLR_GRAY), 0);
+    lv_obj_set_width(lbl_date, SCR_W);
+    lv_obj_set_style_text_align(lbl_date, LV_TEXT_ALIGN_CENTER, 0);
+    lv_obj_align(lbl_date, LV_ALIGN_TOP_MID, 0, 456);
 
     /* ────────────────────────────────────────────────────────────── */
     /*  ERROR OVERLAY  (hidden by default)                           */
@@ -281,10 +291,14 @@ void ui_set_sd(uint64_t used_mb, uint64_t total_mb)
     }
     lv_bar_set_value(bar_sd, pct, LV_ANIM_OFF);
 
-    float used_gb  = used_mb  / 1024.0f;
+    /* Format with one decimal using integer math (LVGL builtin sprintf
-    float total_gb = total_mb / 1024.0f;
+       may lack %f support) */
-    lv_label_set_text_fmt(lbl_sd_info, "%.1f / %.1f GB",
+    uint32_t used_gb_i  = (uint32_t)(used_mb  / 1024);
-                          (double)used_gb, (double)total_gb);
+    uint32_t used_gb_f  = (uint32_t)((used_mb  % 1024) * 10 / 1024);
+    uint32_t total_gb_i = (uint32_t)(total_mb / 1024);
+    uint32_t total_gb_f = (uint32_t)((total_mb % 1024) * 10 / 1024);
+    lv_label_set_text_fmt(lbl_sd_info, "%lu.%lu / %lu.%lu GB",
+                          used_gb_i, used_gb_f, total_gb_i, total_gb_f);
     lv_label_set_text_fmt(lbl_sd_pct, "%d%%", pct);
 
     /* bar turns red when storage > 90% */