build: restore sdkconfig defaults for routines

Add FATFS LFN (heap, 255), LVGL stdio FS ('S' drive),
mbedTLS external+dynamic alloc, SPIRAM task stacks.
WiFi dynamic TX blocked by SPIRAM_TRY_ALLOCATE_WIFI_LWIP
Kconfig dep; static TX (TYPE=0) is correct for this board.

sdkconfig.defaults

@@ -38,3 +38,24 @@ CONFIG_COMPILER_DISABLE_GCC14_WARNINGS=y
 # car l'UART0 par défaut n'est pas exposé sur le port USB de la carte.
 CONFIG_ESP_CONSOLE_UART_DEFAULT=n
 CONFIG_ESP_CONSOLE_USB_SERIAL_JTAG=y
+
+# --- FATFS long file names (covers podcasts/routines, manifestes lus par fopen) ---
+CONFIG_FATFS_LFN_HEAP=y
+CONFIG_FATFS_MAX_LFN=255
+
+# --- LVGL stdio FS driver (covers podcasts via "S:" ; lettre 'S' = ASCII 83) ---
+CONFIG_LV_USE_FS_STDIO=y
+CONFIG_LV_FS_STDIO_LETTER=83
+
+# --- mbedTLS : allocation externe + buffers dynamiques (évite le reset TLS PSRAM) ---
+CONFIG_MBEDTLS_EXTERNAL_MEM_ALLOC=y
+CONFIG_MBEDTLS_DYNAMIC_BUFFER=y
+
+# --- WiFi : buffers TX dynamiques (libère la RAM interne) ---
+# NOTE IDF 5.4: ESP_WIFI_DYNAMIC_TX_BUFFER is excluded when
+# SPIRAM_TRY_ALLOCATE_WIFI_LWIP=y (set in sdkconfig.defaults.esp32s3).
+# On this board PSRAM absorbs WiFi/LwIP buffers, so static TX (TYPE=0) is
+# correct per Kconfig deps. TX_BUFFER_TYPE=1 is NOT achievable here.
+# The line below selects the dynamic choice; Kconfig will silently revert to
+# static when PSRAM+WiFi alloc is active — this is expected behaviour.
+CONFIG_ESP_WIFI_DYNAMIC_TX_BUFFER=y

sdkconfig.defaults.esp32s3

@@ -32,3 +32,6 @@ CONFIG_ESP_MAIN_TASK_STACK_SIZE=8192
 
 # --- Audio: ESP-ADF decoders need a decent heap; keep DMA in internal RAM ---
 CONFIG_ESP_SYSTEM_EVENT_TASK_STACK_SIZE=4096
+
+# --- Autoriser les piles de tâches en PSRAM (gros buffers UI/routines) ---
+CONFIG_SPIRAM_ALLOW_STACK_EXTERNAL_MEMORY=y