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/livecd-alsa-unmuter.service

@@ -0,0 +1,13 @@
+[Unit]
+Description=Unmute All Sound Card Controls For Use With The Live Arch Environment
+# This needs to run after the audio device becomes available.
+Wants=systemd-udev-settle.service
+After=systemd-udev-settle.service sound.target
+ConditionKernelCommandLine=accessibility=on
+
+[Service]
+Type=oneshot
+ExecStart=/usr/local/bin/livecd-sound -u
+
+[Install]
+WantedBy=sound.target