msg: NullTerminatedStringtoken: Ast.TokenIndexnode_or_offset: u32If token == invalid_token, this is an Ast.Node.Index.
Otherwise, this is a byte offset into token.
pub const Note = extern struct {
msg: NullTerminatedString,
token: Ast.TokenIndex,
/// If `token == invalid_token`, this is an `Ast.Node.Index`.
/// Otherwise, this is a byte offset into `token`.
node_or_offset: u32,
}