fix: setup non-root user 1000 in Dockerfile to fix permission errors

Dockerfile

@@ -3,9 +3,12 @@ FROM python:3.10.7-slim
 ENV PYTHONUNBUFFERED=1 \
     PYTHONDONTWRITEBYTECODE=1
 
+# Create a non-root user with UID 1000
+RUN useradd -m -u 1000 user
+
 WORKDIR /app
 
-COPY requirements.txt ./
+COPY --chown=user requirements.txt ./
 RUN apt-get update && apt-get install -y --no-install-recommends \
     git \
     wget \
@@ -18,7 +21,11 @@ RUN apt-get update && apt-get install -y --no-install-recommends \
     && pip install --no-cache-dir -r requirements.txt \
     && python -c "import transformers; print('transformers', transformers.__version__); print('has Sam3Model', hasattr(transformers, 'Sam3Model'))"
 
-COPY . .
+COPY --chown=user . .
+
+USER user
+ENV HOME=/home/user
+ENV PATH=/home/user/.local/bin:$PATH
 
 EXPOSE 7860