iso: fix packages.x86_64 (no inline comments; gstreamer-vaapi -> gst-plugin-va)

Inline comments after a package name broke kitty/flatpak (became invalid
names with trailing whitespace). gstreamer-vaapi was removed from Arch.
calamares is AUR-only -> commented pending a [tanin] rebuild decision.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

iso/build-profile/airootfs/etc/systemd/system/pacman-init.service

@@ -0,0 +1,15 @@
+[Unit]
+Description=Initializes Pacman keyring
+Requires=etc-pacman.d-gnupg.mount
+After=etc-pacman.d-gnupg.mount time-sync.target
+BindsTo=etc-pacman.d-gnupg.mount
+Before=archlinux-keyring-wkd-sync.service
+
+[Service]
+Type=oneshot
+RemainAfterExit=yes
+ExecStart=/usr/bin/pacman-key --init
+ExecStart=/usr/bin/pacman-key --populate
+
+[Install]
+WantedBy=multi-user.target