Feature: Add tracing annotations to generated repository methods.

I'd like to be able to get all my queries (and context) in a single tool like Zipkin. Whether this is an option to the annotation processor or an "always on" thing, I personally don't have a preference.

The issue concerns tracing annotations on generated repository methods and mentions the annotation processor and Zipkin. Start by locating the generated repository method entry points and annotation-processor configuration; done would mean repository queries and their context can be collected by a single tracing tool, with the option behavior decided.

Written by the indexing model from the issue text.