Update instructions on hatch/VScode integration

[grst]

Close #424

For now, environment creation is still a manual step. See also pypa/hatch-code#229

Ideally, at some point we could shorten our instructions in favor of a link to the offical hatch docs: pypa/hatch#2336

[github-actions]

A PR has been generated to the instance repo: scverse/cookiecutter-scverse-instance#294

You can check out the PR to preview your changes in an instance of the cookiecutter template.
It will be kept in sync with this PR automatically.

[flying-sheep]

For troubleshooting, we should also mention that you need

1. vscode-python-environments¹ and hatch-code installed
2. "python.useEnvironmentsExtension": true

There are three code paths in the Python extension:

1. No vscode-python-environments¹: Builtin Hatch support with old code path and interface works
2. (the default for now) Have vscode-python-environments installed and "python.useEnvironmentsExtension": false results in no Hatch integration
3. Have vscode-python-environments and hatch-code installed and "python.useEnvironmentsExtension": true uses the currently best possible Hatch integration using the new interface

Footnotes

1. vscode-python-environments is installed by default when you install the Python extension but some people manually uninstalled it ↩ ↩²

[grst]

Getting quite complicated. Shall we wait for pypa/hatch#2336 and reference that?

[flying-sheep]

No, the explanation is complicated, but I don’t consider these instructions complicated:

you need vscode-python-environments and hatch-code installed and "python.useEnvironmentsExtension": true set.

That’s all very easily verifiable and achievable for any VS Code user.