Move Ranged into ruff_text_size (#6919)

## Summary

The motivation here is that this enables us to implement `Ranged` in
crates that don't depend on `ruff_python_ast`.

Largely a mechanical refactor with a lot of regex, Clippy help, and
manual fixups.

## Test Plan

`cargo test`

crates/ruff_python_parser/src/string.rs

@@ -1,6 +1,6 @@
+use ruff_python_ast::ConversionFlag;
 use ruff_python_ast::{self as ast, BytesConstant, Constant, Expr, StringConstant};
-use ruff_python_ast::{ConversionFlag, Ranged};
-use ruff_text_size::{TextLen, TextRange, TextSize};
+use ruff_text_size::{Ranged, TextLen, TextRange, TextSize};
 
 // Contains the logic for parsing string literals (mostly concerned with f-strings.)
 //