feat: record groups

[AndersDJohnson]

We should support record groups/aliases so that we can store common regexes for --only rules in configuration and refer to them by those aliases.

So that rather than having to write:

mockyeah record --only '(/api/v(.*)/users)|/api/v(.*)/posts)'

We can write:

mockyeah record --groups users,posts

Where we have those regexes defined in config as:

{
  "groups": {
    "users": "/api/v(.*)/users",
    "posts": "/api/v(.*)/posts"
  }
}

We could also use this feature to store recorded fixture data under a subdirectory specific to the group (though not recordings, since they can hit multiple URLs matching multiple groups).