E-ink device optimization / EPUBKit integration

Support for optimizing EPUBs for e-ink devices (like Boox, Remarkable, etc.) and potential integration with tools like EPUBKit (epubkit.ink) that reformat EPUBs for e-ink screens.

This could include features like:

• Export/optimize EPUBs for e-ink display
• Better rendering on e-ink-optimized devices
• Integration with e-ink device ecosystems

Submitted via support email.