ESP8266EX simple HTTP/WWW server

Hardware: ESP8266EX with external 128mbit flash 25Q128FV for firmware files (if necessary) and data storage. ESP8266EX is accepting asynchronous ASCII data on UART port (maximum available standard baudrate) and store the data in text file created in the external flash (25Q128FV). ESP8266EX needs to run the WWW server in the background task offering simple WWW page with text preview of the stored data as well as downloading the data via WWW interface in the form of TXT file. Display or download data range need to be selectable in form of size in bytes or fixed size memory pages if more convenient. Secondary WWW sub page for configuration needs to offer WiFi mode change (AP mode, client mode, SSID, encryption selection and password, IP, GATE, MASK settings or DHCP server enable). In every mode selected, same WWW page needs to be served allowing text view/download and ESP8266EX reconfiguration. ESP8266EX has to initially work in preset AP mode with fixed SSID and fixed IP. Asynchronous UART logging to file has highest priority, drop rate is not acceptable. Display/download option needs to be updated dynamically (with some reasonable period like 5s) by new stored data. This is the basic starter project draft only. Advanced option may be discussed/developed later. Download and configuration WWW pages examples are shown in the file attachments. NodeMCU platform prefered (or other open SDK).