Extend pragma comment cases (#7687)

## Summary

Extends the pragma comment detection in the formatter to support
case-insensitive `noqa` (as supposed by Ruff), plus a variety of other
pragmas (`isort:`, `nosec`, etc.).

Also extracts the detection out into the trivia crate so that we can
reuse it in the linter (see:
https://github.com/astral-sh/ruff/issues/7471).

## Test Plan

`cargo test`

crates/ruff_python_trivia/src/lib.rs

@@ -1,10 +1,12 @@
 mod comment_ranges;
 mod cursor;
+mod pragmas;
 pub mod textwrap;
 mod tokenizer;
 mod whitespace;
 
 pub use comment_ranges::CommentRanges;
 pub use cursor::*;
+pub use pragmas::*;
 pub use tokenizer::*;
 pub use whitespace::*;