初始提交卡包 USB 工程

纳入固件源码、屏幕组件、nand_xfer 工具和文档。忽略本机构建产物、sdkconfig，以及含本机路径的依赖锁。

Co-authored-by: Cursor <[email protected]>

main/NS4168/micro_decoder_wrapper.cpp

@@ -0,0 +1,29 @@
+#include "micro_decoder/decoder_source.h"
+#include "micro_decoder/types.h"
+#include <stdio.h>
+
+static FILE* g_fp = nullptr;
+/*
+extern "C" {
+
+void md_init(const char* path)
+{
+    g_fp = fopen(path, "rb");
+}
+
+int md_read(uint8_t* buf, int len)
+{
+    if (!g_fp) return 0;
+    return fread(buf, 1, len, g_fp);
+}
+
+void md_deinit()
+{
+    if (g_fp) {
+        fclose(g_fp);
+        g_fp = nullptr;
+    }
+}
+
+}
+*/