Increase the verbosity of files fixed from a formatting run

[martinjlowm]

I was troubleshooting some formatting errors with a colleague today and we didn't find the reporting of "Fixed N files" very helpful from a CI job. (the root cause was really a stale pre-commit configuration).

Surely, if you are fixing thousands of files, that won't be super helpful either, so a sane upper limit similar to the reported lint diagnostics would be neat.

Fixed X files, of which Y were:
- A
- B
- C

[arendjr]

Would a summary as discussed here be of help? #57

[martinjlowm]

I believe it would. As long as that summary would include a sane number of files. Perhaps with a programmatic output (thinking JSON), the full list could be presented.

[ematipico]

They seem to be two feature requests:

• present a summary for each command
• dump the output in a format different from just words

They are both tracked.