Support for structured logging (using `log/slog`) about image

[mtrmac]

Thanks for reaching out.

At this point, c/image only requires Go 1.19, so this is not yet possible (a migration to Go 1.20 could happen pretty soon, but we are probably going to be stuck on 1.20 support for the supported lifetime of Fedora 38).

Longer-term, yes, logrus is in maintenance mode, and migrating to the standard-library API is the most obvious replacement choice.

• I think we are fairly unlikely to do a mass-scale logging migration, but requiring new code to use slog would make sense
• The stable API commitment would make it difficult to add some probably desirable features, like callers submitting non-default Logger value, or even providing a context.Context to every log entry. The API can be extended, but again, that would probably only happen over some time.

[cfiderer]

About the support for older Go versions: the github.com/sagikazarmark/slog-shim package provides a means to migrate to slog before adopting Go 1.21.