Initial scaffold: idempotent Sunshine + Moonlight installer for Omarchy

Sets up bidirectional game streaming across Omarchy/Hyprland/Wayland
machines (NVIDIA desktop and AMD Framework laptop), with the Macbook
as an additional Moonlight client.

The same install.sh runs on either machine; GPU vendor is detected at
runtime and the appropriate hardware-encode packages are installed.

Includes:
- KMS capture setup (cap_sys_admin on sunshine, input group, uinput udev rule)
- ufw / firewalld port opening when a firewall is active
- systemd --user service + loginctl enable-linger for always-on hosting
- uninstall.sh with --purge for user data removal
- Flags to install host-only or client-only

lib/detect.sh

@@ -0,0 +1,30 @@
+#!/usr/bin/env bash
+# Detect GPU vendor, session type, hostname.
+
+detect_gpu_vendor() {
+  local vga
+  vga="$(lspci -nn 2>/dev/null | grep -iE 'vga|3d|display' || true)"
+  if grep -qi 'nvidia' <<<"$vga"; then
+    echo "nvidia"
+  elif grep -qiE 'amd|advanced micro devices|ati' <<<"$vga"; then
+    echo "amd"
+  elif grep -qi 'intel' <<<"$vga"; then
+    echo "intel"
+  else
+    echo "unknown"
+  fi
+}
+
+detect_all() {
+  HOSTNAME_SHORT="$(hostname -s 2>/dev/null || hostname)"
+  GPU_VENDOR="$(detect_gpu_vendor)"
+  SESSION_TYPE="${XDG_SESSION_TYPE:-unknown}"
+  export HOSTNAME_SHORT GPU_VENDOR SESSION_TYPE
+
+  if [[ "$SESSION_TYPE" != "wayland" ]]; then
+    warn "Session type is '$SESSION_TYPE' (not wayland). KMS capture still works at the TTY/DRM level, but Hyprland-specific paths assume Wayland."
+  fi
+  if [[ "$GPU_VENDOR" == "unknown" ]]; then
+    warn "Could not detect GPU vendor. Encoder packages will be skipped; HW encode may not work."
+  fi
+}