Developer productivity next

### User Story

As a developer of Sleeper, I want to spend my time as productively as possible, so that I can make more improvements to the system.

### Description / Background

We'd like to make any changes to the system that will save developers time overall, or enable them to improve the system more easily.

This should be issues that can regularly save developer time or make it easier for them to deliver improvements. If they are limited to a specific area of the codebase that is not frequently interacted with, the issue may belong under a more specific parent.

### Technical Notes / Implementation Details

See sub-issues. We may make notes here on potential issues that have not yet been raised, or on priority of the open issues.

Start by reviewing the sub-issues referenced in the description and identify one concrete developer-productivity improvement with a defined scope. The issue does not name files, tests, entry points, or completion criteria, so the parent issue alone is not ready to implement.

Written by the indexing model from the issue text.