Add headless streaming mode + Mac client + full docs

Headless mode (new) — for KVM-attached hosts streaming to disconnected clients
- --headless / --mirror flags; default headless on hostname JARVIS, mirror elsewhere
- New lib/headless.sh installs prep-cmd hooks to ~/.local/share/omarchy-moonlight/bin
- bin/sunshine-stream-do.sh creates/resizes a Hyprland HEADLESS-1 output to the
  connecting client's resolution and migrates the active workspace onto it
- bin/sunshine-stream-undo.sh tears down the headless output on disconnect and
  returns the workspace to a non-headless monitor when one is available
- lib/config.sh writes capture=wlr, output_name=HEADLESS-1, and the JSON
  global_prep_cmd entry referencing the installed hook paths
- lib/preflight.sh adds a preflight_headless step that checks hyprctl, jq, and
  a running Hyprland session (warn-only, install can proceed)
- lib/verify.sh adds checks for the hook scripts and the wlr/global_prep_cmd
  config lines

Mac client
- client/install-macos.sh: Darwin guard, Homebrew presence check, brew cask
  install of Moonlight, idempotent
- client/README.md: per-platform install (macOS / Android / iOS / Apple TV /
  Linux + Steam Deck) and the five-step first-pair walkthrough

Other
- jq added to the helper install set in lib/packages.sh (hooks parse Hyprland
  JSON output)
- README.md rewritten to cover both modes, the new flags, the tuned defaults
  per mode + per vendor, the headless internals, and the client pointer

lib/verify.sh

@@ -67,6 +67,40 @@ verify_install() {
       ;;
   esac
 
+  if [[ "${STREAM_MODE:-}" == "headless" ]]; then
+    local do_script="$HOME/.local/share/omarchy-moonlight/bin/sunshine-stream-do.sh"
+    local undo_script="$HOME/.local/share/omarchy-moonlight/bin/sunshine-stream-undo.sh"
+    local conf="$HOME/.config/sunshine/sunshine.conf"
+
+    if [[ -x "$do_script" ]]; then
+      ok "headless do-hook present and executable"
+    else
+      err "headless do-hook missing or not executable: $do_script"
+      VERIFY_FAILURES=$((VERIFY_FAILURES + 1))
+    fi
+
+    if [[ -x "$undo_script" ]]; then
+      ok "headless undo-hook present and executable"
+    else
+      err "headless undo-hook missing or not executable: $undo_script"
+      VERIFY_FAILURES=$((VERIFY_FAILURES + 1))
+    fi
+
+    if [[ -f "$conf" ]] && grep -q '^capture = wlr' "$conf"; then
+      ok "sunshine.conf has capture = wlr"
+    else
+      err "sunshine.conf missing 'capture = wlr'"
+      VERIFY_FAILURES=$((VERIFY_FAILURES + 1))
+    fi
+
+    if [[ -f "$conf" ]] && grep -q '^global_prep_cmd' "$conf"; then
+      ok "sunshine.conf has global_prep_cmd"
+    else
+      err "sunshine.conf missing 'global_prep_cmd'"
+      VERIFY_FAILURES=$((VERIFY_FAILURES + 1))
+    fi
+  fi
+
   if systemctl --user is-active --quiet sunshine.service; then
     ok "sunshine.service is active"
     if ss -ltn 2>/dev/null | grep -q ':47990 '; then