Draft: feat: use structured logging throughout and use logging interface everywhere

This MR changes the logger interface to better support structured logging, updates calls to logging throughout the project to use this interface. Both in updating the calls to the logging package and by converting logging that called logrus directly to use the logging package.

The logging interface is split out from the dcontext package, as it was a strange addition compared to the other parts of that package and this package was overwhelmingly used across the project only for logging.

There are some opinionated changes to the interface, such as removing the formatting log calls, and restricting adding fields to the logger to only the logger's WithFlields method. Overall, I think these changes add consistency to logging calls.