Dart: class field 'children' list never populated (dead identifier-scan in extractDartClassMembers)

[carlos-alm]

Context

Discovered while implementing #2319 (Dart typeMap population for field/parameter types).

src/extractors/dart.ts's extractDartClassMembers has a "Field declarations" loop meant to push each field into the class definition's children: SubDeclaration[] array (used to list a class's properties, e.g. for codegraph show ClassName-style output):

// Field declarations
for (let j = 0; j < member.childCount; j++) {
  const decl = member.child(j);
  if (decl?.type === 'identifier') {
    children.push({ name: decl.text, kind: 'property', line: member.startPosition.row + 1 });
    break;
  }
}

This scans member's (a declaration node) DIRECT children for a node of type identifier. But for every real Dart field-declaration shape (final Foo x;, Foo x;, late Foo x;, Foo? x;, final Foo a, b;), the field's identifier is nested TWO levels deep — declaration -> initialized_identifier_list -> initialized_identifier -> identifier — never a direct child of declaration itself. Dart requires every field to carry a var/final/const/late/type modifier, so there is no legal field-declaration shape where identifier IS a direct child of declaration.

Confirmed empirically: parsing class UserService { final UserRepository _repo; UserService(this._repo); } and checking symbols.definitions.find(d => d.name === 'UserService').children returns undefined — the field is silently never recorded.

Net effect: Dart class definitions' children array is always empty for real code — this loop is dead code that has presumably never fired since Dart support was added.

Suggested fix direction

Rewrite the loop to walk initialized_identifier_list -> initialized_identifier -> identifier, mirroring the (already-correct) same-shape traversal added in #2319's handleDartFieldDeclTypeMap/extractDartDeclaredTypeName. Also verify/fix the Rust mirror in crates/codegraph-core/src/extractors/dart.rs's extract_dart_class_methods, which has the analogous gap (it currently continues on any class_member that isn't a method/bodyless-signature, without ever recording a field child either).

Low-severity — doesn't affect call resolution or the resolution benchmark, only the children listing on Dart class definitions — but worth fixing since it's presumably surprising to anyone using codegraph show or similar against Dart code today.