On the Ξ Effekt Working Group meeting, we agreed that the tab size should be 2, but by default, VSCode uses tab size set to 4.
It would be nice to investigate whether we can add a default like:

        "editor.tabSize": 2

into the extension so that we can ensure nice formatting. :)

However, we should support an override mechanism for the users who really want 4 spaces per soft tab.

Problem

The extension tries to check every fenced code block in markdown files, regardless of the actual language the block contains.

How to reproduce

Create an arbitrary markdown file (e.g. text.md) and create an arbitrary fenced block within it, e.g.

```
const x = 1
```

here the following linting error is given

string matching regex '//[^\n]*(\n|\z)' expected but 'c' found

Possible solution

Instead of the extension being triggered by every fenced code block in every markdown file, make the extension only sensitive to files with the file extension .effekt.md. This should be specific enough for it not being triggered by accident.

AFAICT, there is currently no way to run Effekt programs from the VS Code GUI. (Apart from opening the terminal and running it directly).

Currently only the generated JavaScript can be shown in the buffer.
We should add a setting to select the backend, so that also the result of other backends can be displayed.

This is helpful both for debugging and for understanding how compilation works.