uxjulia/CrossInk ? reverse-engineered prompt

Build me a firmware for the Xteink X3 and X4, plus the Seeed Studio Sticky, that feels like a better e reader experience than the stock one. I want it to keep the core CrossPoint reader behavior, but with nicer typography, cleaner text rendering, and a few simple reading tools that actually help day to day.

Please include better built in fonts, support for common book text features like underlines, strikethrough, section breaks, tables, bookmarks, and a few optional reading modes like bionic reading and guide dots. I also want lightweight reading stats, finished book tracking, custom sleep screens, and the ability to sync reading progress and all time stats between two devices. If it makes sense, add a small web based way to upload and manage books too.

Make it work well on an ESP32 based e ink device, keep it stable, and prefer practical reading features over flashy extras.