feat(hardware): nomarchy.hardware.* enablement beyond nixos-hardware

The nixos-hardware "common-*" profiles the installer selects cover the
basics (microcode, the Intel/AMD VA-API media stack, weekly fstrim), and
power.nix adds thermald + power-profiles-daemon. This adds the gap above
them, generically and detected at install time.

New modules/nixos/hardware.nix exposes a vendor-keyed nomarchy.hardware.*
surface — broadly-beneficial bits default ON when the vendor is detected
(opt-out), heavy/experimental bits behind opt-in toggles:
  - intel.enable -> GuC/HuC (i915.enable_guc=3); intel.computeRuntime
    (opt-in: intel-compute-runtime + vpl-gpu-rt)
  - amd.enable -> amd_pstate=active + radeonsi VA-API env; amd.rocm.enable
    + amd.rocm.gfxOverride (opt-in: ROCm HIP/OpenCL)
  - fingerprint.enable -> fprintd; fingerprint.pam (opt-in: login + sudo)
  - npu.enable (opt-in/experimental) -> the in-kernel driver
    (amdxdna/intel_vpu) keyed by vendor; userspace runtime is BYO

hardware-db.sh now detects Intel/AMD, a fingerprint reader (libfprint USB
vendor IDs) and an NPU (Intel VPU / AMD XDNA PCI IDs), emitting NOMARCHY
lines the installer bakes into system.nix — safe defaults active, opt-ins
commented. Audited against the commons to avoid double-setting.

Verified: flake check green; a toggles-on build has amd_pstate=active +
i915.enable_guc=3 in kernel-params and ships fprintd.service; detection
runs correctly on the (AMD Ryzen-AI) dev machine. On-hardware verification
of the AMD/NPU/Intel-compute runtime bits is still pending.

Docs: template commented examples, README option table, ROADMAP status.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

pkgs/nomarchy-install/hardware-db.sh

@@ -112,6 +112,7 @@ HARDWARE_DB=(
 # ----------------------------------------------------------------------------
 nomarchy_detect_hw() {
     local sys_vendor product_name cpu_vendor
+    local nvidia=0 amdgpu=0 intelgpu=0
     sys_vendor=$(cat /sys/class/dmi/id/sys_vendor 2>/dev/null || echo "")
     product_name=$(cat /sys/class/dmi/id/product_name 2>/dev/null || echo "")
     cpu_vendor=$(lscpu 2>/dev/null | awk -F: '/Vendor ID/{gsub(/ /,"",$2); print $2; exit}')
@@ -126,7 +127,7 @@ nomarchy_detect_hw() {
 
     # GPU (lspci may list several; report all)
     if command -v lspci >/dev/null 2>&1; then
-        local gpu_line nvidia=0 amdgpu=0 intelgpu=0
+        local gpu_line
         while IFS= read -r gpu_line; do
             case "$gpu_line" in
                 *"[10de:"*|*"NVIDIA"*) nvidia=1 ;;
@@ -140,6 +141,54 @@ nomarchy_detect_hw() {
         (( intelgpu )) && { echo "MODULE common-gpu-intel";  echo "DETAIL gpu: Intel";  detected=1; }
     fi
 
+    # ── nomarchy.hardware.* enablement — the gap ABOVE the nixos-hardware
+    # commons (GuC/HuC, amd-pstate, the AMD VA-API env, GPU-compute runtimes,
+    # fprintd, the NPU driver). Emitted as NOMARCHY lines the installer turns
+    # into nomarchy.hardware.* in system.nix; safe bits active, heavy opt-ins
+    # commented.
+    if [[ "$cpu_vendor" == "GenuineIntel" || $intelgpu -eq 1 ]]; then
+        echo "NOMARCHY hardware.intel.enable=true"
+        echo "DETAIL nomarchy.hardware.intel: GuC/HuC on; GPU-compute runtime opt-in"
+    fi
+    if [[ "$cpu_vendor" == "AuthenticAMD" || $amdgpu -eq 1 ]]; then
+        echo "NOMARCHY hardware.amd.enable=true"
+        echo "DETAIL nomarchy.hardware.amd: amd-pstate + VA-API on; ROCm opt-in"
+    fi
+
+    # Fingerprint reader — libfprint's common USB vendor IDs (Goodix,
+    # Synaptics/Validity, Elan, EgisTec, Upek, AuthenTec, FocalTech, NB).
+    local have_fp=0
+    if command -v lsusb >/dev/null 2>&1; then
+        local vid
+        for vid in 27c6 06cb 138a 04f3 1c7a 147e 08ff 2808 1fae; do
+            lsusb 2>/dev/null | grep -qiE "ID ${vid}:" && { have_fp=1; break; }
+        done
+    else
+        local f
+        for f in /sys/bus/usb/devices/*/idVendor; do
+            [[ -e "$f" ]] || continue
+            case "$(cat "$f" 2>/dev/null)" in
+                27c6|06cb|138a|04f3|1c7a|147e|08ff|2808|1fae) have_fp=1; break ;;
+            esac
+        done
+    fi
+    if [[ $have_fp -eq 1 ]]; then
+        echo "NOMARCHY hardware.fingerprint.enable=true"
+        echo "DETAIL fingerprint reader detected → fprintd (PAM login/sudo opt-in)"
+    fi
+
+    # NPU (detect-only → a commented, experimental opt-in). Intel VPU /
+    # AMD XDNA PCI IDs; best-effort across recent gens.
+    if command -v lspci >/dev/null 2>&1; then
+        if lspci -nn 2>/dev/null | grep -qiE '\[8086:(7d1d|643e|ad1d|b03e)\]'; then
+            echo "NOMARCHY-NPU intel"
+            echo "DETAIL Intel NPU detected (opt-in, experimental)"
+        elif lspci -nn 2>/dev/null | grep -qiE '\[1022:1502\]'; then
+            echo "NOMARCHY-NPU amd"
+            echo "DETAIL AMD XDNA NPU detected (opt-in, experimental)"
+        fi
+    fi
+
     # Chassis (glob test, not compgen — nixpkgs' non-interactive bash
     # is built without the completion builtins)
     local bats=(/sys/class/power_supply/BAT*)