[`perflint`] Catch a wider range of mutations in `PERF101` (#9955)
## Summary
This PR ensures that if a list `x` is modified within a `for` loop, we
avoid flagging `list(x)` as unnecessary. Previously, we only detected
calls to exactly `.append`, and they couldn't be nested within other
statements.
Closes https://github.com/astral-sh/ruff/issues/9925.