Feature: Add conflicts sort

[Zweih]

Users can now sort by the length of conflicts with qp order conflicts, qp order conflicts:asc, or qp order conflicts:desc.

> qp s name,conflicts o conflicts
NAME                    CONFLICTS
yay-bin                 yay
util-linux-libs         libutil-linux
tinysparql              tracker3<=3.7.3-2
systemd-libs            libsystemd
systemd-sysvcompat      sysvinit
src-cli-bin             sourcegraph-cli
at-spi2-core            at-spi2-atk<=2.38.0-2, atk<=2.38.0-2
libverto                krb5<1.19.3-2, libverto-libevent<0.3.2-4
iputils                 arping, netkit-base
qp-git                  qp, qp-bin
procps-ng               procps, sysvinit-tools
poppler                 poppler-qt3<25.03.0, poppler-qt4<25.03.0
vim                     gvim, vim-minimal
util-linux              hardlink, rfkill
ttf-nerd-fonts-symbols  ttf-nerd-fonts-symbols-1000-em, ttf-nerd-fonts-symbols-2048-em
rust                    cargo, rust-docs<1:1.56.1-3, rustfmt
mesa                    libva-mesa-driver<1:24.2.7-1, mesa-libgl<17.0.1-2, mesa-vdpau<1:24.2.7-1
x264                    libx264, libx264-10bit, libx264-all
systemd                 nss-myhostname, systemd-tools, udev
grub                    grub-bios, grub-common, grub-efi-aarch64, grub-emu, grub-legacy

Closes #259