incorporates and implements mobile build service functionality.

backend/Dockerfile

@@ -4,6 +4,11 @@ WORKDIR /app
 
 ENV PYTHONUNBUFFERED=1
 
+# SSH tools for mobile build orchestration (SSH to build host, docker exec into flutter-build container)
+RUN apt-get update && apt-get install -y --no-install-recommends \
+    sshpass openssh-client \
+    && rm -rf /var/lib/apt/lists/*
+
 COPY requirements.txt .
 RUN pip install --no-cache-dir -r requirements.txt
 
@@ -15,5 +20,8 @@ COPY . .
 RUN mkdir -p /app/geo
 COPY geo/ /app/geo/
 
+# Ensure upload/artifact dirs exist at runtime
+RUN mkdir -p /tmp/kmtn_mobile_build_uploads /tmp/kmtn_mobile_build_artifacts
+
 EXPOSE 8000
 CMD ["gunicorn", "app.main:app", "-k", "uvicorn.workers.UvicornWorker", "-b", "0.0.0.0:8000", "--workers", "1", "--timeout", "120"]