update: update docker and readme

DockerFile

@@ -1,6 +1,13 @@
 FROM python:3.10.9
-COPY . .
-WORKDIR /
-RUN pip install --no-cache-dir --upgrade -r /requirements.txt
 
-CMD ["uvicorn", "main:app", "--host", "0.0.0.0", "--port", "7860"]
+RUN useradd -m -u 1000 user
+USER user
+ENV PATH="/home/user/.local/bin:$PATH"
+
+WORKDIR /app
+
+COPY --chown=user ./requirements.txt requirements.txt
+RUN pip install --no-cache-dir --upgrade -r requirements.txt
+
+COPY --chown=user . /app
+CMD ["uvicorn", "app:app", "--host", "0.0.0.0", "--port", "7860"]