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/user/hardware/framework/fix-f13-amd-audio-input.sh

@@ -0,0 +1,5 @@
+AMD_AUDIO_CARD=$(pactl list cards 2>/dev/null | grep -B20 "Family 17h/19h" | grep "Name: " | awk '{print $2}' || true)
+
+if [[ -n $AMD_AUDIO_CARD ]]; then
+  pactl set-card-profile "$AMD_AUDIO_CARD" "HiFi (Mic1, Mic2, Speaker)" 2>/dev/null || true
+fi