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## Summary
Fixes#8334.
`Display` has been implemented for `ruff_workspace::Settings`, which
gives a much nicer and more readable output to `--show-settings`.
Internally, a `display_settings` utility macro has been implemented to
reduce the boilerplate of the display code.
### Work to be done
- [x] A lot of formatting for `Vec<_>` and `HashSet<_>` types have been
stubbed out, using `Debug` as a fallback. There should be a way to add
generic formatting support for these types as a modifier in
`display_settings`.
- [x] Several complex types were also stubbed out and need proper
`Display` implementations rather than falling back on `Debug`.
- [x] An open question needs to be answered: how important is it that
the output be valid TOML? Some types in settings, such as a hash-map
from a glob pattern to a multi-variant enum, will be hard to rework into
valid _and_ readable TOML.
- [x] Tests need to be implemented.
## Test Plan
Tests consist of a snapshot test for the default `--show-settings`
output and a doctest for `display_settings!`.
Micha Reiser
Jane Lewis
Jane Lewis
Zanie Blue
konsti
Charlie Marsh