feat: 大屏后端（FastAPI+MQTT+sim_engine）

- REST :10085 / MQTT 控制 / SSE 回退 / AI+语音
- 数据源规划：接核心服务端 + 算力引擎真实数据

backend/vendor/s2s-cloud/Dockerfile

@@ -0,0 +1,27 @@
+FROM nvidia/cuda:12.8.1-cudnn-runtime-ubuntu24.04
+
+ENV DEBIAN_FRONTEND=noninteractive
+ENV PYTHONUNBUFFERED=1
+ENV PATH="/usr/src/app/.venv/bin:${PATH}"
+
+WORKDIR /usr/src/app
+
+# Install packages
+RUN apt-get update \
+    && apt-get install -y --no-install-recommends \
+        ca-certificates \
+        git \
+        libportaudio2 \
+        libsndfile1 \
+        python3 \
+        python3-pip \
+        python3-venv \
+    && rm -rf /var/lib/apt/lists/*
+RUN python3 -m pip install --no-cache-dir --break-system-packages uv
+
+COPY pyproject.toml README.md LICENSE MANIFEST.in ./
+RUN uv sync --python /usr/bin/python3 --no-install-project --no-dev
+
+COPY . .
+RUN uv sync --python /usr/bin/python3 --no-dev
+RUN python -c "import nltk; nltk.download('punkt_tab'); nltk.download('averaged_perceptron_tagger_eng')"