Not exactly what I’m thinking either, but look at how concise pgaccess (for postgresql) was.
However you will only get to see AOLServer's source code, as the latter two were proprietary.
Tcl/Tk makes UI's that jar in an ugly, immediately recognisable as "old-fashioned" way. This matters to users whether we like it or not. It would be a very niche commercial software project that used it for its UI no matter how beautifully elegant the functionality of its UI. Best ever UI will still elicit an "Ew, yuk." From the majority of its users.
Graphical UIs have been de rigeur for what, 30+ years? We still suck at the tools to program them which are all a pain in the backside to use even when making something very simple and expected. We still suck at programming these UIs when we use them. All of them. I have no answers to this.
It's also really easy to create truly ugly (but functional) GUIs in Tcl/Tk.
Yes, and they are thousand time more usable that the "modern" crap.
GUI design is going backwards since 10 years.
Guis have always been more discoverable and just better for certain tasks, usually where you want to see something with immediate updatable feedback but the gui libraries have always been terrible. They were terrible 30 years ago, and 20 and 10 and still today.
I don't have answers.
1. a package manager
2. language server
3. a vs code plugin or an emacs mode for the language server
And as for language server—yeah, not gonna happen.