Add hardware layout docs and PERC H730 non-RAID setup script

Initial structure for R730xd passthrough configuration:
- README with VM layout table and setup order
- docs/hardware-layout.md: bay/GPU/USB mapping worksheet
- scripts/perc-nonraid.sh: convert H730 drives to per-disk non-RAID mode

https://claude.ai/code/session_01TxTSnxDjgEVuNztdsWQjMD

docs/hardware-layout.md

@@ -0,0 +1,65 @@
+# Hardware Layout
+
+Dell R730xd — fill this in after running `scripts/build-bay-map.sh`.
+
+## Bay → Device → VM Map
+
+Run `scripts/build-bay-map.sh` on the Proxmox host to auto-populate the by-id column.
+Confirm bay numbers by running `ledctl locate=<device>` to blink the drive LED.
+
+| Bay | Assigned VM | Size | /dev/disk/by-id (fill in) | Notes |
+|-----|-------------|------|---------------------------|-------|
+| 1   | 100         |      |                           |       |
+| 2   | 100         |      |                           |       |
+| 3   | 100         |      |                           |       |
+| 4   | 100         |      |                           |       |
+| 5   | 100         |      |                           |       |
+| 6   | 100         |      |                           |       |
+| 7   | 100         |      |                           |       |
+| 8   | 100         |      |                           |       |
+| 9   | 101         |      |                           |       |
+| 10  | 101         |      |                           |       |
+| 11  | 102         |      |                           |       |
+| 12  | 102         |      |                           |       |
+
+## GPU Map
+
+Run `lspci -nn | grep -i nvidia` on the Proxmox host and fill in the PCI addresses.
+
+| Slot | PCI Address (fill in) | Assigned VM | Notes |
+|------|-----------------------|-------------|-------|
+| GPU 1 |                      | 100         | Frigate decode + display |
+| GPU 2 |                      | 101         |       |
+
+The GPU's HDMI audio function (same address, function 1) must be passed through alongside the GPU.
+Example: GPU at `01:00.0` → also pass `01:00.1`.
+
+## USB / TPU Map
+
+| Device | VID:PID | Assigned VM | Notes |
+|--------|---------|-------------|-------|
+| Coral (pre-init)  | 1a6e:089a | 100 | Global Unichip — before first inference |
+| Coral (post-init) | 18d1:9302 | 100 | Google — after first inference; pass both |
+
+## IOMMU Groups
+
+Run on Proxmox host to check groupings before passthrough:
+
+```bash
+for d in /sys/kernel/iommu_groups/*/devices/*; do
+  n=${d#*/iommu_groups/*}; n=${n%%/*}
+  printf 'IOMMU Group %s ' "$n"
+  lspci -nns "${d##*/}"
+done | sort -V
+```
+
+Each GPU should appear in its own group (with only its HDMI audio sibling).
+If a GPU shares a group with other devices, those must be passed through together.
+
+## Network
+
+| VM  | Interface | Bridge | Notes |
+|-----|-----------|--------|-------|
+| 100 | net0      | vmbr0  |       |
+| 101 | net0      | vmbr0  |       |
+| 102 | net0      | vmbr0  |       |