Parse comments in go.mod files for "// indirect"

We should parse comments in go.mod files for "// indirect" line-trailing comments that indicates that a package is the results of a transitive dependency resolution as opposed to be a directly added dependency. There may be other comments too.

Here the comments essentially become "API" in the go.mod format, and can respect https://www.hyrumslaw.com/

And there are folks that rely on this too: https://github.com/search?q="%2F%2F+indirect"+language%3APython+"go.mod"&type=code