Fix Dockerfile for Hugging Face build

Dockerfile

@@ -1,70 +1,43 @@
-# --- Stage 1: Build Frontend ---
+# ---------- Stage 1: Build Frontend ----------
 FROM node:20-slim AS build-frontend
 WORKDIR /app/frontend
-<<<<<<< HEAD
-# Optimize by copying only package files first
-=======
->>>>>>> origin/main
+
+# Copy only package files first (better caching)
 COPY frontend/package*.json ./
-RUN npm install
+
+# Use npm ci for reproducible HF builds
+RUN npm ci
+
+# Copy frontend source
 COPY frontend/ ./
+
+# Build frontend (Vite → dist)
 RUN npm run build
 
-# --- Stage 2: Final Image ---
+
+# ---------- Stage 2: Final Image ----------
 FROM python:3.11-slim
-<<<<<<< HEAD
-# Hugging Face Spaces runtime requirement: user 1000
+
+# Create HF-compatible user (required)
 RUN useradd -m -u 1000 user
 USER user
-ENV PATH="/home/user/.local/bin:$PATH"
-WORKDIR /app
 
-# Install system dependencies
-USER root
-=======
+ENV PATH="/home/user/.local/bin:$PATH"
 WORKDIR /app
 
-# Install system dependencies for PDF and ML
->>>>>>> origin/main
-RUN apt-get update && apt-get install -y \
-    build-essential \
-    libpq-dev \
-    && rm -rf /var/lib/apt/lists/*
-<<<<<<< HEAD
-USER user
-
-# Install Python requirements
-COPY --chown=user:user backend/requirements.txt ./
-RUN pip install --no-cache-dir --upgrade pip && \
-    pip install --no-cache-dir -r requirements.txt && \
-    pip install --no-cache-dir gunicorn
-
-# Copy backend code
-COPY --chown=user:user backend/ ./
+# Install backend dependencies + gunicorn
+COPY --chown=user backend/requirements.txt ./requirements.txt
+RUN pip install --no-cache-dir -r requirements.txt gunicorn
 
-# Copy built frontend to backend's build folder
-COPY --chown=user:user --from=build-frontend /app/frontend/dist ./build
-=======
+# Copy backend source
+COPY --chown=user backend/ ./
 
-# Copy backend requirements and install
-COPY backend/requirements.txt ./
-RUN pip install --no-cache-dir -r requirements.txt
-RUN pip install gunicorn
+# Copy frontend build output
+COPY --from=build-frontend --chown=user /app/frontend/dist ./build
 
-# Copy backend code
-COPY backend/ ./
-
-# Copy built frontend from Stage 1 to backend's build folder
-# Note: server.py expects the React app in a 'build' folder
-COPY --from=build-frontend /app/frontend/dist ./build
->>>>>>> origin/main
-
-# Set Environment Variables
+# Hugging Face required port
 ENV PORT=7860
-ENV PYTHONUNBUFFERED=1
-
-# Expose the port HF Spaces expects
 EXPOSE 7860
 
-# Run the server using gunicorn
+# Start backend
 CMD ["gunicorn", "--bind", "0.0.0.0:7860", "--timeout", "120", "--workers", "1", "server:server"]