It's difficult to run tests with coverage reports for all packages locally and review the results

To run tests for all packages and see coverage reports, you can say:

```
yarn test:verbose
```

But this essentially runs a separate instance of `jest` per package. If any package fails — meaning that if any test for any package fails, or the coverage check fails — then you must scroll up to find which package failed.

It would be nice to be able to run tests for all packages still in parallel, but then combine results together and provide some kind of summary at the end. Perhaps this is something that can help: https://stackoverflow.com/a/62603091/260771

Start with the `yarn test:verbose` command and inspect how it launches a separate Jest instance for each package. Review the linked Stack Overflow approach, then define a parallel run that combines coverage and test results into a final package-level failure summary; done means failures and coverage problems are visible without scrolling through the full output.

Written by the indexing model from the issue text.