Fix Dockerfile: Install dependencies as root to avoid permission errors

Dockerfile

@@ -1,10 +1,10 @@
 FROM python:3.9
 
-# Set working directory to the user's home/app
-WORKDIR /home/user/app
+# Workdir for build steps
+WORKDIR /code
 
-# Install system dependencies for opencv and ffmpeg
-# We do this as root before switching users
+# Install system dependencies (Run as ROOT)
+# This ensures we have permission to install system packages
 USER root
 RUN apt-get update && apt-get install -y \
     ffmpeg \
@@ -12,25 +12,33 @@ RUN apt-get update && apt-get install -y \
     libxext6 \
     && rm -rf /var/lib/apt/lists/*
 
-# Create a non-root user (required by HF Spaces)
+# Copy requirements file
+COPY requirements.txt /code/requirements.txt
+
+# Install Python dependencies globally (Run as ROOT)
+# Installing as root avoids permission issues with /home/user/.local
+RUN pip install --no-cache-dir --upgrade -r /code/requirements.txt
+
+# Create a non-root user (Required by Hugging Face Spaces)
 RUN useradd -m -u 1000 user
 
-# Switch to the new user
+# Switch to the non-root user for the application runtime
 USER user
-ENV PATH="/home/user/.local/bin:$PATH"
+ENV HOME=/home/user \
+    PATH=/home/user/.local/bin:$PATH
 
-# Copy the current directory contents into the container at /home/user/app
-# using --chown to ensure the user owns the files
-COPY --chown=user . .
+# Set working directory to the user's home/app
+WORKDIR $HOME/app
 
-# Install python dependencies
-RUN pip install --no-cache-dir --upgrade -r requirements.txt
+# Copy the application code (Run as USER)
+# We change ownership to the user so they can read/write if needed
+COPY --chown=user . $HOME/app
 
-# Download models during build so they are cached in the image
-# This will save them to /home/user/.u2net
+# Download models (Run as USER)
+# This ensures models are saved to /home/user/.u2net, which the app can read
 RUN python download_models.py
 
-# Expose the port (Hugging Face Spaces defaults to 7860)
+# Expose the application port
 EXPOSE 7860
 
 # Command to run the application