More user friendly about using mirror

[July541]

I'm not sure it is worth it because we don't have many mirrors, but at least let me write sth.

1. Try to use a mirror if the default connection gets lost.
2. Add a subcommand like ghcup mirror to list all available mirrors or specify a mirror.
3. Integrate with Create 'ghcup healthcheck' command #701, suggest using a mirror if network issues.

[hasufell]

Mirror support has already been overhauled, so it might not be that difficult, see #700

[July541]

Can you please clarify, what so it might not be that difficult mean? Does it mean we should keep the current state?

[hasufell]

I don't know man. See the PR. You can already define arbitrary mirrors. Suggest a specific user experience/API if you have one.

[hasufell]

Ok, sorry for the flippant comments. I didn't have a great week.

Let's go over it one by one:

Try to use a mirror if the default connection gets lost.

That makes sense, but in order to do that, we first need:

1. an actual mirror (I had plans to prototype that... but I never got around it)
2. a way to turn this behavior off... some users might now want this behavior. And then the question is also: should this be default?

Add a subcommand like ghcup mirror to list all available mirrors or specify a mirror.

I can imagine:

1. ghcup mirror list [--country=<country>]
2. ghcup mirror set <mirror|default>
3. ghcup mirror test with latency information

Integrate with #701, suggest using a mirror if network issues

Possible, if we ever implement the healthcheck.