docs: rewrite root and MethodD README for demo

Author: zheyuliu328

Dockerfile

@@ -0,0 +1,20 @@
+FROM python:3.11-slim
+
+ENV PYTHONDONTWRITEBYTECODE=1
+ENV PYTHONUNBUFFERED=1
+
+WORKDIR /workspace
+
+RUN apt-get update && apt-get install -y --no-install-recommends \
+    build-essential \
+    gcc \
+    git \
+    curl \
+    && rm -rf /var/lib/apt/lists/*
+
+COPY MethodD/requirements.txt /tmp/requirements.txt
+RUN pip install --no-cache-dir -r /tmp/requirements.txt
+
+COPY . /workspace
+
+CMD ["/bin/bash"]