* docs: add custom titlebar example * docs: add links and other small edits * docs: add panel window docs * docs: remove panel example * docs: specify expected emphasis style * docs: responding to feedback * docs: fix section names in links * docs: rework baseWindow note * docs: making window customization its own section * responding to feedback Co-authored-by: trop[bot] <37223003+trop[bot]@users.noreply.github.com> Co-authored-by: Anny Yang <anny@electronjs.org>