Fix formatter inserting blank line between doc comment and attribute on TupleTypeDecl

`get_item_first_line` was missing the `TupleTypeDecl` case, causing it to
use the item's own span line instead of the attribute line. This made
`format-wado` add a blank line between `/// Doc` and `#[comp_feature(...)]`
on every run, failing the CI integrity check.

https://claude.ai/code/session_0181NuipeuMorkJgDi4dh3Dp

Author: claude

wado-compiler/src/unparse.rs

@@ -2648,6 +2648,7 @@ fn get_item_first_line(item: &Item) -> usize {
             .as_deref()
             .and_then(|a| a.first().map(|a| a.span.line)),
         Item::Trait(t) => first_attr_line(&t.attrs),
+        Item::TupleTypeDecl(d) => first_attr_line(&d.attrs),
         _ => None,
     };
     attr_line.unwrap_or(item_line).min(item_line)

wado-compiler/tests/format.rs

@@ -884,6 +884,20 @@ fn test_format_deref_method_preserves_parens() {
     );
 }
 
+#[test]
+fn test_format_doc_comment_before_attribute_no_extra_blank() {
+    // Doc comment immediately before an attribute must not grow a blank line
+    let source = "/// Doc\n#[comp_feature(\"tuple\")]\npub type [..T];\n";
+    let formatted = wado_compiler::format(source).expect("format failed");
+    assert!(
+        !formatted.contains("/// Doc\n\n#["),
+        "doc comment + attribute must not have a blank line between them: {}",
+        formatted
+    );
+    let formatted2 = wado_compiler::format(&formatted).expect("format failed");
+    assert_eq!(formatted, formatted2, "format should be idempotent");
+}
+
 #[test]
 fn test_format_idempotent_all_fixtures() {
     let fixtures_dir = Path::new(env!("CARGO_MANIFEST_DIR")).join("tests/fixtures");