Profile trim: swap firefox->falkon, plasma->plasma-meta, drop mpv

- firefox (286 MiB) -> falkon (16 MiB): -270 MiB, KDE-native browser
- plasma group (665 MiB) -> plasma-meta (328 MiB): -337 MiB, drops
  unneeded wallpapers, X11-only packages, and dev tools
- mpv removed: -30 MiB, music preview feature long gone

ISO estimated ~2.8 GB -> ~2.15 GB, matching Artix Plasma size.

iso-profiles/antergos/live-overlay/etc/calamares/modules/netinstall.yaml

@@ -14,7 +14,7 @@
     - antergos-next-keyring
     - antergos-wallpapers
     - antergos-grub-theme
-    - firefox
+    - falkon
     - mesa
     - mesa-utils
     - networkmanager

iso-profiles/antergos/profile.yaml

@@ -22,9 +22,8 @@ rootfs:
   packages:
     - antergos-release
     - qt6-multimedia-ffmpeg
-    - firefox
+    - falkon
     - vlc
-    - mpv
     - calamares
     - calamares-branding-antergos-next
     - antergos-welcome
@@ -85,7 +84,7 @@ livefs:
     - virtualbox-guest-utils
     - broadcom-wl
     - antergos-grub-theme
-    - plasma
+    - plasma-meta
     - ark
     - dolphin
     - ffmpegthumbs