KDE: It goes to 6!

This megacommit merges all the work from https://github.com/freebsd/freebsd-ports-kde/tree/kde-it_goes_to_6
Specifically:
- KDE Plasma 6 ports updated to 6.2.5
- KDE Applications ports updated to 24.12.0
- Development ports of KDE Applications removed
- A lot of various ports switched to Qt 6 by default
- Some KDE Frameworks 5 and Plasma 5 ports are adapted to be coinstallable
  with their 6 counterparts

PR:		284351
Exp-run by:	antoine
Pull Request:	https://github.com/freebsd/freebsd-ports/pull/341

Co-authored-by:	Max Brazhnikov <makc@FreeBSD.org>
Co-authored-by:	Kenneth Raplee <kenrap@kennethraplee.com>
Co-authored-by:	Jason E. Hale <jhale@FreeBSD.org>
Co-authored-by:	Gleb Popov <arrowd@FreeBSD.org>

math/labplot/Makefile

@@ -41,12 +41,13 @@ DATADIR=	${PREFIX}/share/labplot2
 
 OPTIONS_DEFINE=		CANTOR FITS FFTW3 HDF5 LIBCERF MATLAB NETCDF ORCUS \
 			ORIGINLAB READSTAT
-OPTIONS_DEFAULT=	${OPTIONS_DEFINE}
+OPTIONS_DEFAULT:=	${OPTIONS_DEFINE:NCANTOR}
 
 CANTOR_DESC=		KDE Cantor support
 CANTOR_LIB_DEPENDS=	libcantorlibs.so:math/cantor \
 			libspectre.so:print/libspectre
 CANTOR_CMAKE_BOOL=	ENABLE_CANTOR
+CANTOR_IGNORE=		has to be ported to KF6/Qt6 for Cantor support
 
 FFTW3_DESC=		Speedier FFTs in the numerical and stats lib (NSL)
 FFTW3_LIB_DEPENDS=	libfftw3.so:math/fftw3