vendor : update cpp-httplib to 0.40.0 (#21100)

Signed-off-by: Adrien Gallouët <angt@huggingface.co>

vendor/cpp-httplib/httplib.h

@@ -8,8 +8,8 @@
 #ifndef CPPHTTPLIB_HTTPLIB_H
 #define CPPHTTPLIB_HTTPLIB_H
 
-#define CPPHTTPLIB_VERSION "0.39.0"
-#define CPPHTTPLIB_VERSION_NUM "0x002700"
+#define CPPHTTPLIB_VERSION "0.40.0"
+#define CPPHTTPLIB_VERSION_NUM "0x002800"
 
 #ifdef _WIN32
 #if defined(_WIN32_WINNT) && _WIN32_WINNT < 0x0A00
@@ -1266,6 +1266,7 @@ struct Request {
   bool is_multipart_form_data() const;
 
   // private members...
+  bool body_consumed_ = false;
   size_t redirect_count_ = CPPHTTPLIB_REDIRECT_MAX_COUNT;
   size_t content_length_ = 0;
   ContentProvider content_provider_;
@@ -1475,6 +1476,8 @@ using SocketOptions = std::function<void(socket_t sock)>;
 
 void default_socket_options(socket_t sock);
 
+bool set_socket_opt(socket_t sock, int level, int optname, int optval);
+
 const char *status_message(int status);
 
 std::string to_string(Error error);
@@ -1564,6 +1567,13 @@ ssize_t write_headers(Stream &strm, const Headers &headers);
 bool set_socket_opt_time(socket_t sock, int level, int optname, time_t sec,
                          time_t usec);
 
+size_t get_multipart_content_length(const UploadFormDataItems &items,
+                                    const std::string &boundary);
+
+ContentProvider
+make_multipart_content_provider(const UploadFormDataItems &items,
+                                const std::string &boundary);
+
 } // namespace detail
 
 class Server {