Change: Don't use 'server address' string in server list when displaying an invite code (#9615)

src/lang/english.txt

@@ -2257,6 +2257,7 @@ STR_NETWORK_SERVER_LIST_LANDSCAPE                               :{SILVER}Landsca
 STR_NETWORK_SERVER_LIST_MAP_SIZE                                :{SILVER}Map size: {WHITE}{COMMA}x{COMMA}
 STR_NETWORK_SERVER_LIST_SERVER_VERSION                          :{SILVER}Server version: {WHITE}{RAW_STRING}
 STR_NETWORK_SERVER_LIST_SERVER_ADDRESS                          :{SILVER}Server address: {WHITE}{RAW_STRING}
+STR_NETWORK_SERVER_LIST_INVITE_CODE                             :{SILVER}Invite code: {WHITE}{RAW_STRING}
 STR_NETWORK_SERVER_LIST_START_DATE                              :{SILVER}Start date: {WHITE}{DATE_SHORT}
 STR_NETWORK_SERVER_LIST_CURRENT_DATE                            :{SILVER}Current date: {WHITE}{DATE_SHORT}
 STR_NETWORK_SERVER_LIST_GAMESCRIPT                              :{SILVER}Game Script: {WHITE}{RAW_STRING} (v{NUM})

src/network/network_gui.cpp

@@ -681,7 +681,8 @@ public:
 			y += FONT_HEIGHT_NORMAL;
 
 			SetDParamStr(0, sel->connection_string);
-			DrawString(r.left + WD_FRAMERECT_LEFT, r.right - WD_FRAMERECT_RIGHT, y, STR_NETWORK_SERVER_LIST_SERVER_ADDRESS); // server address
+			StringID invite_or_address = StrStartsWith(sel->connection_string, "+") ? STR_NETWORK_SERVER_LIST_INVITE_CODE : STR_NETWORK_SERVER_LIST_SERVER_ADDRESS;
+			DrawString(r.left + WD_FRAMERECT_LEFT, r.right - WD_FRAMERECT_RIGHT, y, invite_or_address); // server address / invite code
 			y += FONT_HEIGHT_NORMAL;
 
 			SetDParam(0, sel->info.start_date);