Allow any instead of custom *Author type

[meatballhat]

What type of PR is this?

• cleanup

What this PR does / why we need it:

Drop the custom *Author type and allow any with the assumption that it either implements fmt.Stringer or can otherwise be safely Sprintf'd via %s.

Which issue(s) this PR fixes:

Supports #1586 given the *Author type was defined in app.go which is slated for removal.

[asahasrabuddhe]

This looks good. Why are the tests failing though?

[abitrolly]

@asahasrabuddhe looks like net/mail adds 500kB to the size of the package.

[meatballhat]

@asahasrabuddhe @abitrolly I introduced this because I generally consider using an existing standard library type to be preferable to maintaining our own. Considering the increase in binary size, and that we're not going to be attempting to directly send email with the result of *mail.Address.String, I'm leaning towards not making this change. WDYT?

[abitrolly]

@meatballhat I think like this issue needs to be addressed upstream somehow. Implementing interface for storing two strings should not result in 500kB increase. Why does this happen?

[meatballhat]

@meatballhat I think like this issue needs to be addressed upstream somehow. Implementing interface for storing two strings should not result in 500kB increase. Why does this happen?

@abitrolly wow, yeah, I hadn't thought of it that way!

[asahasrabuddhe]

This change does not make sense considering the increase in binary size. If we find a way like implementing an interface which is still compatible with the standard library and also does not affect the binary size, that's the way to go.

[dearchap]

@meatballhat Just revert to old struct it was just 2 fields. Simple and direct or make an interface and add an example in docs of how to use mail.Address with it.

[meatballhat]

@dearchap I think now that I'd like to use Authors []any given that the values are only ever passed to Sprintf-like functions with %s anyway. I'd like to keep reducing the surface area as much as possible, and making such a change would support that effort. WDYT?

[dearchap]

@meatballhat That would be fine.