The initial "resolved" value of the forward reference is Alignment.default.
pub fn alignmentForwardReference(b: *Builder) Allocator.Error!Alignment.Lazy
pub fn alignmentForwardReference(b: *Builder) Allocator.Error!Alignment.Lazy {
const index = b.alignment_forward_references.items.len;
try b.alignment_forward_references.append(b.gpa, .default);
return .fromFwdRefIndex(index);
}