Add set_basic_auth and set_bearer_token_auth to WebSocketClient (#2652)

ClientImpl and SSLClient let callers set origin credentials with
set_basic_auth()/set_bearer_token_auth(), but WebSocketClient could only
take a fixed Authorization header through its constructor. Add both
setters: each connect() adds the Authorization header to the upgrade
request from the current credentials (Basic over Bearer), unless the
constructor headers already carry one, and never to the proxy's CONNECT
request.

httplib.h

@@ -4768,6 +4768,9 @@ public:
   void
   set_tunnel_hostname_addr_map(std::map<std::string, std::string> addr_map);
 
+  void set_basic_auth(const std::string &username, const std::string &password);
+  void set_bearer_token_auth(const std::string &token);
+
   void set_proxy(const std::string &host, int port);
   void set_proxy_basic_auth(const std::string &username,
                             const std::string &password);
@@ -4841,6 +4844,10 @@ private:
   // Hostname to CONNECT target map, used only through a proxy.
   std::map<std::string, std::string> tunnel_addr_map_;
 
+  std::string basic_auth_username_;
+  std::string basic_auth_password_;
+  std::string bearer_token_auth_token_;
+
   std::string proxy_host_;
   int proxy_port_ = -1;
   std::string proxy_basic_auth_username_;
@@ -23990,6 +23997,9 @@ inline void WebSocketClient::prepare_default_headers(Request &req) {
   }
 
   detail::add_default_user_agent_header(req);
+  detail::add_authorization_header(req, basic_auth_username_,
+                                   basic_auth_password_,
+                                   bearer_token_auth_token_, false);
 }
 
 inline Result WebSocketClient::connect() {
@@ -24212,6 +24222,16 @@ inline bool WebSocketClient::connect_with_proxy(Response &proxy_res,
   return true;
 }
 
+inline void WebSocketClient::set_basic_auth(const std::string &username,
+                                            const std::string &password) {
+  basic_auth_username_ = username;
+  basic_auth_password_ = password;
+}
+
+inline void WebSocketClient::set_bearer_token_auth(const std::string &token) {
+  bearer_token_auth_token_ = token;
+}
+
 inline void WebSocketClient::set_proxy(const std::string &host, int port) {
   proxy_host_ = host;
   proxy_port_ = port;