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/calamares/modules/packages.conf

@@ -0,0 +1,12 @@
+---
+backend: pacman
+pacman:
+  num_retries: 3
+  disable_download_timeout: true
+  needed_only: false
+operations:
+# Strip the live-only installer from the installed target. Everything else was
+# cloned by unpackfs.
+- try_remove:
+  - calamares
+  - cage