There’s a reason the milk man used to deliver every day

but then you wouldn’t know that Edge runs perfectly well on Linux too lol I use Edge every day on Linux without issue but only for work related stuff

For the server I’ve used gogs for many years. It was easy to set up and has a web interface. What client you use is really up to you with git.

https://gogs.io/

you mentioned you’ve used joplin. All my notes are in markdown and I’ve been using Obsidian instead. Obsidian includes support for mermaid and can render (relatively simple) flowcharts.

https://obsidian.md/ https://mermaid.js.org/syntax/flowchart.html