Make setup ISO-only

Remove legacy online installer entrypoints, collapse migrations for 4.0, and move setup responsibilities into target-side system, hardware, and user commands.

install/hardware/intel/video-acceleration.sh

@@ -0,0 +1,11 @@
+# This installs hardware video acceleration for Intel GPUs
+
+if INTEL_GPU=$(lspci | grep -iE 'vga|3d|display' | grep -i 'intel'); then
+  # HD Graphics / Iris / Xe / Arc / Non-Arc Panther Lake use intel-media-driver + VPL
+  if [[ ${INTEL_GPU,,} =~ (hd\ graphics|uhd\ graphics|xe|iris|arc|panther\ lake) ]]; then
+    omarchy-pkg-add intel-media-driver libvpl vpl-gpu-rt
+  elif [[ ${INTEL_GPU,,} =~ "gma" ]]; then
+    # Older generations from 2008 to ~2014-2017 use libva-intel-driver
+    omarchy-pkg-add libva-intel-driver
+  fi
+fi