Update case synopsis, split description into paragraphs, improve markup,
light wordsmithing, and import exit status line from NetBSD.
While here, remove the '-' from the beginning of this document.
PR: 298329
Event: EuroBSDcon 2026
Fixes: c9afaa6389 ("Add case statement fallthrough")
Fixes: f7a9b7fe3a ("Allow a left parenthesis before patterns in case blocks")
Fixes: e00e16ad7f ("Allow empty case/esac statements")
MFC after: 3 days
Reviewed by: bcr, jilles, Artem Bunichev <[email protected]>
Differential Revision: https://reviews.freebsd.org/D59518
Alexander Ziaee
35973eceff