media-gfx/ipe: fix missing desktop eclass inherit and lint

media-gfx/ipe: fix missing desktop eclass inherit and lint

All non-9999-* versions call make_desktop_entry in src_install but
never inherit the desktop eclass that defines it, which would die at
install time. Add it to the inherit line across all versions. Also
reorder S/LICENSE/SLOT/KEYWORDS/IUSE/RESTRICT to the conventional
order, drop a double blank line, and document the highprec USE flag
plus the remote-id in metadata.xml.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>