fix(packaging): autoload vhci-hcd and open its attach files for the usbip Deck pad

Steam Input only adopts the virtual Steam Deck controller when it arrives as
a real USB device (raw_gadget or usbip/vhci transports); the UHID fallback
has no USB interface and Steam ignores it. On a stock host neither
precondition for usbip held: vhci-hcd isn't loaded, and its sysfs
attach/detach files are root-only while the host runs as a user service —
so every session silently fell back to UHID and 'no controller appears on
the host' (live-debugged 2026-07-08: client events all arrived, the pad
existed, Steam just refused it).

Ship both preconditions with the host packages:
 * modules-load.d/punktfunk.conf loads vhci-hcd at boot (rpm/deb/arch;
   Bazzite gets it via the RPM payload + a modprobe in the sysext
   post-merge hook)
 * a udev rule in 60-punktfunk.rules grants the input group write on
   vhci_hcd's attach/detach whenever the device appears

Verified end-to-end on a live host: usbip in-process attach, hid-steam
binds all three interfaces, 'Steam Deck' + motion evdev appear, and Steam
adopts the pad (client-mode grab + its own virtual X360 emission).

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

packaging/arch/PKGBUILD

@@ -98,6 +98,8 @@ package_punktfunk-host() {
   install -Dm0755 "$T/punktfunk-host"                 "$pkgdir/usr/bin/punktfunk-host"
   # /dev/uinput + /dev/uhid -> input group (virtual gamepads + DualSense UHID)
   install -Dm0644 "$R/scripts/60-punktfunk.rules"     "$pkgdir/usr/lib/udev/rules.d/60-punktfunk.rules"
+  # vhci-hcd autoload — usbip transport for the virtual Steam Deck pad (Steam only adopts USB pads)
+  install -Dm0644 "$R/scripts/punktfunk-modules.conf" "$pkgdir/usr/lib/modules-load.d/punktfunk.conf"
   # 32 MB UDP socket buffers (send-side headroom at high bitrate)
   install -Dm0644 "$R/scripts/99-punktfunk-net.conf"  "$pkgdir/usr/lib/sysctl.d/99-punktfunk-net.conf"
   # systemd USER units (the host runs in the graphical session, not as root); repoint ExecStart.

packaging/bazzite/punktfunk-sysext.sh

@@ -77,6 +77,10 @@ post_merge() {
   for f in /usr/lib/sysctl.d/99-punktfunk-net.conf /usr/lib/sysctl.d/99-punktfunk-client-net.conf; do
     [ -f "$f" ] && sysctl -q -p "$f" 2>/dev/null || :
   done
+  # vhci-hcd now, no reboot (modules-load.d/punktfunk.conf covers boot): the usbip transport
+  # that makes the virtual Steam Deck pad a real USB device Steam Input adopts. The udev add
+  # event fires the 60-punktfunk.rules vhci rule, opening the attach files to the input group.
+  [ -f /usr/lib/modules-load.d/punktfunk.conf ] && modprobe vhci-hcd 2>/dev/null || :
   # The /etc payload a sysext can't carry. The gamescope-session drop-in is %config(noreplace):
   # only seed it, never clobber a local edit. The tray autostart entry is not user config.
   if [ -f "$ETC_SRC/gamescope-session-plus/sessions.d/steam" ] \

packaging/debian/build-deb.sh

@@ -42,6 +42,8 @@ SHAREDIR="$STAGE/usr/share/$PKG"
 # --- file layout (matches the RPM %install) ----------------------------------
 install -Dm0755 "$BIN"                              "$STAGE/usr/bin/$PKG"
 install -Dm0644 scripts/60-punktfunk.rules         "$STAGE/usr/lib/udev/rules.d/60-punktfunk.rules"
+# vhci-hcd autoload — usbip transport for the virtual Steam Deck pad (Steam only adopts USB pads).
+install -Dm0644 scripts/punktfunk-modules.conf     "$STAGE/usr/lib/modules-load.d/punktfunk.conf"
 # UDP socket-buffer tuning (32 MB) — without it the kernel clamps the host's SO_SNDBUF to ~416 KB
 # and high-bitrate frames overflow it (send-side packet loss). systemd-sysctl applies it at boot.
 install -Dm0644 scripts/99-punktfunk-net.conf      "$STAGE/usr/lib/sysctl.d/99-punktfunk-net.conf"

packaging/rpm/punktfunk.spec

@@ -195,6 +195,10 @@ install -Dm0755 target/release/punktfunk-host %{buildroot}%{_bindir}/punktfunk-h
 # udev rule — /dev/uinput access for virtual gamepads (input group).
 install -Dm0644 scripts/60-punktfunk.rules %{buildroot}%{_udevrulesdir}/60-punktfunk.rules
 
+# vhci-hcd autoload — the usbip transport that makes the virtual Steam Deck controller a
+# real USB device (Steam Input only adopts those; the UHID fallback is invisible to Steam).
+install -Dm0644 scripts/punktfunk-modules.conf %{buildroot}%{_prefix}/lib/modules-load.d/punktfunk.conf
+
 # UDP socket-buffer tuning (32 MB) — without it the kernel clamps the host's SO_SNDBUF to ~416 KB
 # and high-bitrate frames overflow it (send-side loss). systemd-sysctl applies it at boot.
 install -Dm0644 scripts/99-punktfunk-net.conf %{buildroot}%{_prefix}/lib/sysctl.d/99-punktfunk-net.conf
@@ -309,6 +313,7 @@ install -Dm0644 web/web.env.example                %{buildroot}%{_datadir}/punkt
 %{_bindir}/punktfunk-host
 %{_bindir}/punktfunk-tray
 %{_udevrulesdir}/60-punktfunk.rules
+%{_prefix}/lib/modules-load.d/punktfunk.conf
 %{_prefix}/lib/sysctl.d/99-punktfunk-net.conf
 %{_prefix}/lib/firewalld/services/punktfunk-gamestream.xml
 %{_prefix}/lib/firewalld/services/punktfunk-native.xml