Embed Website HTML into ESP01 (ESP8266) Flash Mem w/ PROGMEM & use JS Fetch API to serve HTTP async

How to insert embed website html page file into ESP01 (ESP8266) flash mem (program space) flash storage with #PROGMEM raw literal via #arduino IDE and using js JavaScript Fetch api to serves HTTP #async requests for monitoring measurement of hx711 1kg load cell weight sensor panel display scale asynchronously.
ESP--01 (ESP8266) is in Access Point (AP) mode wifi open local network serving end user client request via web browser.

start from scratch: