[port] adapt RealSense container to G1 hardware (D435i FW 05.15.x)

The G1's head camera is a D435i (USB 3.2, FW 05.15.01.55) — same family
as the H1's D435 but on a different bus and with older firmware. The
existing image opened the device but wait_for_frames timed out
indefinitely; this turned out to be a librealsense v2.55.x regression
against the D4xx firmware on this robot. Pinning the SDK back to v2.50.0
(the version known to work on the host install at /home/unitree/librealsense)
restores frame delivery.

While in there, refactor the runtime stage to copy librealsense2.so.*
straight from the builder instead of apt-installing it, so the binding
ABI always matches the .so version. Also drop the now-unused Intel apt
repo + GPG key dance.

Frontend stage removed: npm-in-docker can't resolve registry.npmjs.org
on this Jetson (docker's default DNS 127.0.0.53 doesn't work from inside
containers). Build the React app on the host one-shot via:
  docker run --rm --dns 8.8.8.8 -v $(pwd)/src/frontend/react:/app \\
    -w /app node:22-alpine sh -c 'npm install && npm run build'
then `docker compose build` just copies the prebuilt dist/.

Tested on the G1: all REST endpoints (rgb, depth, depth/color, capture,
intrinsics, pointcloud, measure, snapshot) return 200 with valid
payloads at 640x480@30 via USB 3.2.

Note: requires videohub_pc4 stopped (it holds /dev/video4):
  /unitree/sbin/mscli stopservice video_hub_pc4

.dockerignore

@@ -8,3 +8,6 @@ tests/
 docs/
 *.md
 src/libascam_bridge.so
+# Frontend dev artifacts (we copy only dist/ which is built on host)
+src/frontend/react/node_modules/
+src/frontend/react/.vite/

Dockerfile

@@ -8,7 +8,11 @@
 # ---------------------------------------------------------------------------
 FROM ubuntu:22.04 AS librealsense-builder
 ENV DEBIAN_FRONTEND=noninteractive
-ARG RS_VERSION=v2.55.1
+# Pinned to v2.50.0: this is the version proven to work with the D435i
+# firmware 05.15.x shipped on the G1 robot. v2.55+ opens the device but
+# wait_for_frames times out (likely an interaction between the newer USB
+# backend and the older D4xx firmware).
+ARG RS_VERSION=v2.50.0
 
 RUN apt-get update && apt-get install -y --no-install-recommends \
         git cmake build-essential pkg-config ca-certificates \
@@ -33,56 +37,43 @@ RUN cmake .. \
     && make -j$(nproc) \
     && make install
 
-# librealsense@v2.55.1 has a buggy install rule that doesn't install the
-# main pyrealsense2.so — only pyrsutils.so. We pick the main .so straight
-# from the build dir to work around it.
-RUN mkdir -p /opt/pyrealsense2 \
-    && cp -r /usr/lib/python3/dist-packages/pyrealsense2/. /opt/pyrealsense2/ \
-    && cp /src/librealsense/build/Release/pyrealsense2.cpython-310-aarch64-linux-gnu.so /opt/pyrealsense2/ \
-    && ls /opt/pyrealsense2/pyrealsense2.cpython-310-aarch64-linux-gnu.so > /dev/null \
-    && printf 'from .pyrealsense2 import *\n' > /opt/pyrealsense2/__init__.py \
-    && echo "=== /opt/pyrealsense2 contents ===" \
-    && ls -la /opt/pyrealsense2
+# Collect both the python bindings and the native runtime .so. We copy them
+# from the builder stage rather than apt-installing librealsense2 in the
+# runtime stage, so the .so version always matches the bindings.
+RUN mkdir -p /opt/pyrealsense2 /opt/librealsense-runtime \
+    && cp -r /usr/lib/python3/dist-packages/pyrealsense2/. /opt/pyrealsense2/ 2>/dev/null || true \
+    && find /src/librealsense/build -name 'pyrealsense2*.so' -exec cp {} /opt/pyrealsense2/ \; \
+    && find /src/librealsense/build -name 'librealsense2.so*' -exec cp -P {} /opt/librealsense-runtime/ \; \
+    && ( [ -f /opt/pyrealsense2/__init__.py ] || printf 'from .pyrealsense2 import *\n' > /opt/pyrealsense2/__init__.py ) \
+    && echo "=== /opt/pyrealsense2 ===" && ls -la /opt/pyrealsense2 \
+    && echo "=== /opt/librealsense-runtime ===" && ls -la /opt/librealsense-runtime
 
 # ---------------------------------------------------------------------------
-# Stage 2: build React frontend
-# ---------------------------------------------------------------------------
-FROM node:20-alpine AS frontend-build
-WORKDIR /app
-COPY src/frontend/react/package*.json ./
-RUN npm ci
-COPY src/frontend/react/ .
-RUN npm run build
-
-# ---------------------------------------------------------------------------
-# Stage 3: runtime image
+# Stage 2: runtime image
+#
+# Note: the React frontend is built on the host (npm in the Jetson's Docker
+# can't reach registry.npmjs.org — systemd-resolved stub at 127.0.0.53
+# doesn't work inside containers). Build with:
+#   docker run --rm --dns 8.8.8.8 -v $(pwd)/src/frontend/react:/app \
+#     -w /app node:22-alpine sh -c 'npm install && npm run build'
+# Then `docker compose build` just copies the prebuilt dist/.
 # ---------------------------------------------------------------------------
 FROM ubuntu:22.04 AS runtime
 ENV DEBIAN_FRONTEND=noninteractive
 
 RUN apt-get update && apt-get install -y --no-install-recommends \
-        ca-certificates curl gnupg \
+        ca-certificates \
         python3 python3-pip python3-venv \
         libusb-1.0-0 libudev1 \
         libgl1 libglib2.0-0 libsm6 libxext6 libxrender1 \
         usbutils \
     && rm -rf /var/lib/apt/lists/*
 
-# Intel RealSense apt repo for the librealsense2 native runtime (pinned to v2.55.1).
-# Intel rotated the signing key in 2025: the legacy librealsense.pgp file on
-# their server is the old 2018 key (C8B3A55A...), but the current `jammy`
-# Packages index is signed by the new key FB0B24895113F120. We fetch the new
-# key from Ubuntu's keyserver and dearmor it into the trusted keyring.
-RUN mkdir -p /etc/apt/keyrings \
-    && curl -fsSL "https://keyserver.ubuntu.com/pks/lookup?op=get&search=0xFB0B24895113F120" \
-       | gpg --dearmor -o /etc/apt/keyrings/librealsense.gpg \
-    && echo "deb [signed-by=/etc/apt/keyrings/librealsense.gpg] https://librealsense.intel.com/Debian/apt-repo jammy main" \
-        > /etc/apt/sources.list.d/librealsense.list \
-    && apt-get update \
-    && apt-get install -y --no-install-recommends \
-        librealsense2=2.55.1-0~realsense.3337 \
-        librealsense2-udev-rules=2.55.1-0~realsense.3337 \
-    && rm -rf /var/lib/apt/lists/*
+# librealsense native runtime — copied straight from the builder stage so
+# the .so version matches the python bindings exactly (see RS_VERSION above
+# for why we don't apt-install).
+COPY --from=librealsense-builder /opt/librealsense-runtime/ /usr/local/lib/
+RUN ldconfig
 
 # Python bindings (built in stage 1). System Python 3.10 looks in
 # /usr/lib/python3/dist-packages, so install there.
@@ -103,7 +94,7 @@ RUN pip3 install --no-cache-dir \
 
 # Application source
 COPY src/backend/ src/backend/
-COPY --from=frontend-build /app/dist src/frontend/react/dist/
+COPY src/frontend/react/dist/ src/frontend/react/dist/
 
 # Entrypoint
 COPY scripts/entrypoint.sh /app/entrypoint.sh