[blob-service] Introduce S3-specific error types

Summary: Part of ENG-2398 - replaces anyhow with S3 S3-specific error types. Old follow-up to blob service refactor, but will be useful with upcoming changes, and also in the future for telemetry.

Test Plan: Tested together with next diffs

Reviewers: jon, varun, michal

Reviewed By: jon

Subscribers: ashoat, tomek

Differential Revision: https://phab.comm.dev/D8100