torvalds/uemacs — reverse-engineered prompt

I want you to turn this repo into a working old school terminal text editor that I can build and use easily on a modern Unix like Linux or macOS. Keep the spirit of the original uEmacs, small, fast, portable, full screen, keyboard driven, and make sure the classic editing features still work, like opening and saving files, searching, incremental search, multiple buffers and windows, paragraph justify, filename completion, screen resizing, and file locking.

Please clean up whatever is needed so it compiles from the included source and Makefile, starts reliably in a terminal, and includes sensible defaults and basic usage help. If there are outdated assumptions from old systems, modernize them carefully without turning it into a different editor. I would also like the character handling to be reasonable today, especially since there is UTF 8 related code and a demo file in here.

Add a short README section with simple build and run instructions, and look up current terminal portability docs online if you need to.