feat(deploy): enable Hailo/CSI system packages for the offline install

Create the venv with --system-site-packages so it can import the Pi system packages
that are not pip wheels (hailo_platform via hailo-all, picamera2 via python3-picamera2).
Add CAMERA_BACKEND/CSI_DEVICE to the env template and document the Hailo-8 + CSI
prerequisites and air-gap handling in deploy/README.

deploy/README.md

@@ -79,8 +79,40 @@ model (`/opt/move-detect/models/movenet_lightning.onnx`).
 - [ ] Pull the network cable → events keep queueing (`QUEUE_DB` grows) → restore
       → the queue flushes. (End-to-end behavior verified in the edge e2e harness.)
 
+## Hailo-8 HAT + CSI camera path (optional, faster)
+
+The default bundle runs CPU MoveNet + USB webcam. To use the Hailo-8 accelerator
+and/or a CSI camera, add these SYSTEM packages on the Pi (they are apt packages, not
+pip wheels — the venv sees them because it is created with `--system-site-packages`):
+
+```bash
+sudo apt install -y hailo-all python3-picamera2 python3-opencv
+```
+
+- `hailo-all` — HailoRT runtime + driver + the Python `hailo_platform` bindings.
+- `python3-picamera2` — CSI camera stack (libcamera).
+
+Then place the pose model and switch backends in `/etc/move-detect/edge.env`:
+
+```ini
+POSE_BACKEND=hailo
+HAILO_HEF=/opt/move-detect/models/yolov8s_pose.hef   # copy the compiled HEF here
+CAMERA_BACKEND=csi
+CSI_DEVICE=0
+```
+
+Validate on device per `docs/hardware-bringup.md` before trusting output (the Hailo
+decode is unit-locked, but the HailoRT inference + picamera2 color order are hardware-
+validated). USB webcam stays available anytime via `CAMERA_BACKEND=uvc`.
+
+> **Air gap:** `hailo-all` / `python3-picamera2` are the ONE piece this bundle can't
+> carry (Hailo's own driver + apt tree). Pre-install them on the Pi image, or transfer
+> their `.deb`s separately, before running `install_offline.sh`. The pose HEF is
+> likewise supplied out-of-band (compiled from the Hailo Model Zoo).
+
 ## Not bundled (by design)
 
 - **MySQL / the cloud app** — a separate host; see `cloud/docs/cloud-deploy.md`.
-- **HailoRT + `yolov8s_pose.hef`** — the Hailo runtime and HEF are installed via
-  Hailo's own Pi packages; the CPU MoveNet path here needs neither.
+- **HailoRT + `yolov8s_pose.hef` + picamera2** — Hailo's runtime/driver, the compiled
+  HEF, and the CSI camera stack are Pi system packages installed out-of-band (above);
+  the default CPU MoveNet + USB path needs none of them.

deploy/bundle/install_offline.sh

@@ -40,7 +40,13 @@ cp "$HERE/models/"*.onnx "$PREFIX/models/"
 cp "$HERE/docs/"*.md "$PREFIX/docs/" 2>/dev/null || true
 
 echo ">> [3/6] python venv + offline wheel install (--no-index)"
-python3 -m venv "$PREFIX/venv"
+# --system-site-packages so the venv can import the Pi SYSTEM packages that are NOT
+# pip-installable: hailo_platform (HailoRT, apt: hailo-all) for POSE_BACKEND=hailo, and
+# picamera2 (apt: python3-picamera2) for CAMERA_BACKEND=csi. The wheelhouse install
+# below adds our deps into the venv; where a system copy already satisfies a wheel's
+# version constraint pip keeps it (ABI-compatible on the target images), otherwise the
+# bundled wheel installs into the venv and shadows the system copy.
+python3 -m venv --system-site-packages "$PREFIX/venv"
 "$PREFIX/venv/bin/pip" install --no-index --find-links "$WHEELHOUSE" --upgrade pip >/dev/null 2>&1 || true
 "$PREFIX/venv/bin/pip" install --no-index --find-links "$WHEELHOUSE" "${RUNTIME_PKGS[@]}"
 

deploy/systemd/move-detect-edge.env.example

@@ -22,8 +22,12 @@ POSE_BACKEND=movenet
 MOVENET_ONNX=/opt/move-detect/models/movenet_lightning.onnx
 # HAILO_HEF: required when POSE_BACKEND=hailo (uncomment and set).
 #HAILO_HEF=/opt/move-detect/models/yolov8s_pose.hef
+# CAMERA_BACKEND: "uvc" (USB webcam, uses UVC_DEVICE) or "csi" (Pi CSI camera, uses CSI_DEVICE).
+CAMERA_BACKEND=uvc
 # UVC_DEVICE: OpenCV VideoCapture index for the USB (UVC) webcam.
 UVC_DEVICE=0
+# CSI_DEVICE: picamera2 camera_num for the CSI camera (used when CAMERA_BACKEND=csi).
+CSI_DEVICE=0
 # TARGET_FPS: frame pacing = 1/TARGET_FPS.
 TARGET_FPS=12