macOS: drive the install and all customization from a Recovery "PE", no GUI

Replace the screenshot/OCR/keystroke driving of Apple's Recovery with a
"PE": BaseSystem.dmg (a journaled HFS+ volume, writable from Linux) with one
LaunchDaemon added (makeRecoveryPE) that runs /Volumes/VMIX/run.sh as root at
boot, records the status and powers off. launchd loads it alongside its signed
cache (verified on Tahoe 26.6.2); same idea as AutoNBI/Imagr NetBoot images.

- makeImage: the PE runs vmix-install.sh (erase, installer app, SharedSupport
  pkgdmg, startosinstall). Progress is read from the serial console
  (boot-args serial=3 -v, VMIX-* markers) and screenshots (brightness only).
  Fully offline; prepare now takes ~5 min instead of ~10.
- customizeImage: boots the PE with the image attached and runs the template
  offline against the mounted System/Data volumes; OpenCore ScanPolicy
  restricted to HFS+/SATA so only the PE can boot. One PE boot ~30 s. The
  installed macOS is never booted for customization, so nothing depends on
  launchd/BTM approval or a first-boot agent (removed).
- templates rewritten for offline use: generalize creates the user with
  dscl -f (admin, home, auto-login kcpassword, Setup Assistant suppression,
  hostname, locale, timezone, keyboard type, container resize); remote-access,
  no-updates, performance edit the target's plists.
- makeBootDisk: build-time OpenCore variant (serial console, ScanPolicy).
- vm-driver.py rewritten: passive observation only (serial markers, kernel
  boots, panics, brightness), disk+serial-aware hang watchdog, reboot-death
  reset, halt/loginwindow detection. No OCR/tesseract.
- OpenCore: four SMBIOS DIMMs for MacPro7,1 (no "Memory Modules
  Misconfigured" warning).
- tools/soak.sh: repeatability harness.

Verified on daku: base install 23 min end to end; basic + generalize in three
~30 s PE boots; the result auto-logs into the desktop with the created user.

Root cause of the "first-boot hang" (from the serial log): the guest's restart
path panics (IOPlatformHaltRestartAction -> AppleSMC, SMCWDT smcWriteKey
kSMCBadCommand, nested panic) because the pinned OSX-KVM Lilu disables itself
on macOS 26, so VirtualSMC never loads. Handled by the driver (reset within
60 s); kext update to follow.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01XsESshRCoBoUVWV9qKURUF

lib/images/macos/helpers/qemu.nix

@@ -30,6 +30,9 @@ rec {
   sataDrive = { id, port, file, format ? "qcow2", extra ? "" }:
     "-drive id=${id},if=none,format=${format},file=${file}${extra} -device ide-hd,bus=sata.${toString port},drive=${id}";
 
+  # XNU logs to COM1 with boot-args serial=3; the build drivers read this file
+  serialArgs = file: "-serial file:${file}";
+
   firmwareArgs = varsFile:
     "-drive if=pflash,format=raw,readonly=on,file=${pkgs.OVMF.fd}/FV/OVMF_CODE.fd -drive if=pflash,format=raw,file=${varsFile}";
 }