## Summary
We now list each changed file when running with `--check`.
Closes https://github.com/astral-sh/ruff/issues/7782.
## Test Plan
```
❯ cargo run -p ruff_cli -- format foo.py --check
Compiling ruff_cli v0.0.292 (/Users/crmarsh/workspace/ruff/crates/ruff_cli)
rgo + Finished dev [unoptimized + debuginfo] target(s) in 1.41s
Running `target/debug/ruff format foo.py --check`
warning: `ruff format` is a work-in-progress, subject to change at any time, and intended only for experimentation.
Would reformat: foo.py
1 file would be reformatted
```