Implement template strings (#17851)

This PR implements template strings (t-strings) in the parser and
formatter for Ruff.

Minimal changes necessary to compile were made in other parts of the code (e.g. ty, the linter, etc.). These will be covered properly in follow-up PRs.

crates/ruff_python_parser/src/parser/statement.rs

@@ -3012,7 +3012,6 @@ impl<'src> Parser<'src> {
                             // test_ok param_with_annotation
                             // def foo(arg: int): ...
                             // def foo(arg: lambda x: x): ...
-                            // def foo(arg: (x := int)): ...
 
                             // test_err param_with_invalid_annotation
                             // def foo(arg: *int): ...
@@ -3703,6 +3702,7 @@ impl<'src> Parser<'src> {
             | TokenKind::Complex
             | TokenKind::String
             | TokenKind::FStringStart
+            | TokenKind::TStringStart
             | TokenKind::Lbrace
             | TokenKind::Tilde
             | TokenKind::Ellipsis