fix(theme): hide Swage logo in reader view to prevent overlap (#8842)
Reader view sets .aside.visible { padding-top: 0 } (swage.css:1236), so when
the sidebar is open the absolute-positioned logo lands on the Subscription
management button. Extending the existing hide rule from #8739 to also
cover body.reader is the smallest fix; the logo isn't load-bearing in
reader view. Closes #8802.
Co-authored-by: Bjørn A. Andersen <polybjorn@users.noreply.github.com>