ycm-core/YouCompleteMe ? reverse-engineered prompt

Build me a Vim code completion plugin that feels fast and automatic while I type.

I want it to show smart suggestions without me having to press a special shortcut, and let me accept the best match with Tab. It should work for normal identifier based completion in any language, and also support smarter language aware completion for common languages like C, C++, Python, Go, JavaScript, TypeScript, Rust, Java, and C sharp, plus a general fallback for other languages through language servers.

It should also show inline help like diagnostics, signature hints, and simple semantic highlighting when possible. Make it installable with a straightforward setup script, and include clear docs for how to use it in Vim. If you need to check current docs or tooling details online while building it, go ahead and look them up.