Display a message with options when default Mac interpreter is selected

[DonJayamanne]

Fixes #1689

• Pull request represents a single change (i.e. not fixing disparate/unrelated things in a single PR)
• Title summarizes what is changing
• Has a news entry file (remember to thank yourself!)
• Has unit tests & system/integration tests
• [n/a] Any new/changed dependencies in package.json are pinned (e.g. "1.2.3", not "^1.2.3" for the specified version)
• [n/a] package-lock.json has been regenerated by running npm install (if dependencies have changed)

[DonJayamanne]

@d3r3kk
I'd like to change the commands to actual objects than have separate command handlers. I.e. command object will have a handle method.
Didn't make that change now, as it would add noise to the PR.
Once you've review the PR and feel its warranted, then we can proceed on that (either in this same PR or later).

[d3r3kk]

Looks good. I really do like how you've devised the diagnostics routines for the extension. File naming is one of the things I've not yet fully come to terms yet with in this codebase - most of the codebases I've worked on previously have a 1:1 relationship between class defined within.

[d3r3kk]

One question here: Why don't we name the files with the name of the class defined within it? Makes it a bit more discoverable to find things using Ctrl+p instead of Ctrl+Shift+f then searching...

[d3r3kk]

(Not a blocker, just asking why)

[DonJayamanne]

No reason, just that in JS/TS I haven't come across this rule.

[d3r3kk]

That's totally fair, and what I expected. I am 100% certain that the rules in my prior codebases were enforced socially, perhaps canonically-ish in C#/C++.

[d3r3kk]

I'd like to change the commands to actual objects than have separate command handlers. I.e. command object will have a handle method.

Yes, please do open a different PR for the change you describe here. Would like to chat about it with you first to get an understanding of what you mean. (I think I follow, but want to be sure).