Implement visitation of type aliases and parameters (#5927)

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## Summary

<!-- What's the purpose of the change? What does it do, and why? -->

Part of #5062 
Requires https://github.com/astral-sh/RustPython-Parser/pull/32

Adds visitation of type alias statements and type parameters in class
and function definitions.

Duplicates tests for `PreorderVisitor` into `Visitor` with new
snapshots. Testing required node implementations for the `TypeParam`
enum, which is a chunk of the diff and the reason we need `Ranged`
implementations in
https://github.com/astral-sh/RustPython-Parser/pull/32.

## Test Plan

<!-- How was it tested? -->

Adds unit tests with snapshots.

crates/ruff_python_formatter/src/comments/visitor.rs

@@ -3,7 +3,7 @@ use std::iter::Peekable;
 use ruff_text_size::{TextRange, TextSize};
 use rustpython_parser::ast::{
     Alias, Arg, ArgWithDefault, Arguments, Comprehension, Decorator, ElifElseClause, ExceptHandler,
-    Expr, Keyword, MatchCase, Mod, Pattern, Ranged, Stmt, WithItem,
+    Expr, Keyword, MatchCase, Mod, Pattern, Ranged, Stmt, TypeParam, WithItem,
 };
 
 use ruff_formatter::{SourceCode, SourceCodeSlice};
@@ -291,6 +291,13 @@ impl<'ast> PreorderVisitor<'ast> for CommentsVisitor<'ast> {
         }
         self.finish_node(elif_else_clause);
     }
+
+    fn visit_type_param(&mut self, type_param: &'ast TypeParam) {
+        if self.start_node(type_param).is_traverse() {
+            walk_type_param(self, type_param);
+        }
+        self.finish_node(type_param);
+    }
 }
 
 fn text_position(comment_range: TextRange, source_code: SourceCode) -> CommentLinePosition {