spoof: spoof-mode master fork (none/hyperv/vbs/physical) + microsoft-vm persona

Phase 0. Replace the spoof-hv knob with spoof-mode, a first-class selector modeled as
two axes (persona x presence) exposed as 4 presets:
- none: stock (spoof_on now requires mode != none, killing half-spoof states)
- hyperv: Microsoft Virtual Machine persona + Hyper-V presence (honest child VM)
- vbs (seeded default): real-OEM persona + Hyper-V presence (mimic physical Win11+VBS)
- physical: real-OEM persona + bare metal

Engine: spoof_mode()/spoof_persona_msvm()/spoof_presence_hyperv() in spoof-core; the
hv/waet/pvpanic/vmgenid policies now derive from the mode. microsoft-vm persona wired
across platform (ACPI OEM VRTUAL/MICROSFT, Microsoft Corporation), system type1
(Virtual Machine), storage (Virtual HD / Msft Virtual DVD-ROM) and EDID (MSF/Hyper-V).
New getters spoof_system_manufacturer/product (type1, real-OEM or Hyper-V). Patches:
0002 registers spoof-mode; 0024 now also forces type1 system identity. spoof-hv kept
as a back-compat alias. Inert without a seed.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

README.md

@@ -38,6 +38,21 @@ QEMU_SPOOF_SEED=<string>                     # env fallback (testing)
 Same seed → same persona. Mix in a host secret so personas are not guessable from
 the vmid. Proxmox: add `spoof-seed=` through the VM `args:` line.
 
+### Modes
+
+`-machine ...,spoof-mode=` selects the identity strategy (two axes — hardware
+persona × hypervisor presence — as presets):
+
+| mode | persona | presence | looks like |
+|---|---|---|---|
+| `none` | stock | KVM | a plain VM (no spoof) |
+| `hyperv` | Microsoft "Virtual Machine" | Hyper-V | an honest Hyper-V guest |
+| `vbs` (default when seeded) | real OEM | Hyper-V | a physical Win11 box with VBS on |
+| `physical` | real OEM | bare metal | a physical machine (no hypervisor) |
+
+The presence axis (clearing the hypervisor bit / Hyper-V enlightenments) is partly
+the CPU model configuration (`cpu: host,hidden=1` + `hv-*`); set it to match the mode.
+
 ## Layout
 
 ```