lib/SD: Arduino-ESP32 3.3.12's SD library, as it comes

A project library named SD takes the framework's place at link time.
Unchanged here (Apache-2.0), so that the next commit shows exactly what
roro9stack changes in it, and a later framework update can be compared.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01EhqxQ49eCju4CzKYNjZzwT

lib/SD/src/sd_defines.h

@@ -0,0 +1,25 @@
+// Copyright 2015-2016 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+#ifndef _SD_DEFINES_H_
+#define _SD_DEFINES_H_
+
+typedef enum {
+  CARD_NONE,
+  CARD_MMC,
+  CARD_SD,
+  CARD_SDHC,
+  CARD_UNKNOWN
+} sdcard_type_t;
+
+#endif /* _SD_DISKIO_H_ */