Add Dockerfile for HuggingFace Spaces deployment

Dockerfile

@@ -0,0 +1,89 @@
+# Multi-stage build for NullAI Phi-4 Knowledge System
+# Optimized for HuggingFace Spaces deployment
+
+# Stage 1: Build frontend
+FROM node:18-alpine AS frontend-builder
+
+WORKDIR /app/frontend
+
+# Copy package files
+COPY frontend/package*.json ./
+
+# Install dependencies
+RUN npm ci --only=production
+
+# Copy frontend source
+COPY frontend/ ./
+
+# Build frontend
+RUN npm run build
+
+# Stage 2: Python backend
+FROM python:3.11-slim
+
+LABEL maintainer="Kodai Motonishi <kodai820820@gmail.com>"
+LABEL description="NullAI Phi-4 14B Knowledge Management System"
+
+WORKDIR /app
+
+# Install system dependencies
+RUN apt-get update && apt-get install -y \
+    gcc \
+    g++ \
+    make \
+    curl \
+    && rm -rf /var/lib/apt/lists/*
+
+# Copy backend requirements
+COPY backend/requirements.txt ./backend/
+
+# Install Python dependencies
+RUN pip install --no-cache-dir --upgrade pip && \
+    pip install --no-cache-dir -r backend/requirements.txt
+
+# Copy backend code
+COPY backend/ ./backend/
+
+# Copy frontend build from previous stage
+COPY --from=frontend-builder /app/frontend/dist ./frontend/dist
+
+# Copy configuration files
+COPY models_config.json domains_config.json null_ai_config.json* ./
+
+# Copy utility scripts (optional)
+COPY db_manager.py* inference_engine_unified.py* runner_engine.py* ./ || true
+
+# Copy import tools
+COPY import_iath.py batch_import_iath.sh ./
+
+# Create necessary directories
+RUN mkdir -p /app/data /app/uploads
+
+# Set environment variables for HuggingFace Spaces
+ENV PYTHONPATH=/app
+ENV PYTHONUNBUFFERED=1
+ENV HOST=0.0.0.0
+ENV PORT=7860
+
+# Database configuration
+ENV DATABASE_URL=sqlite:////app/data/nullai_knowledge.db
+
+# Security settings
+ENV SECRET_KEY=changeme-in-production
+
+# CORS settings (will be updated in Spaces)
+ENV CORS_ORIGINS='["https://kofdai-nullai-knowledge-system.hf.space"]'
+
+# Expose port (HuggingFace Spaces standard)
+EXPOSE 7860
+
+# Health check
+HEALTHCHECK --interval=30s --timeout=10s --start-period=10s --retries=3 \
+    CMD curl -f http://localhost:7860/api/system/health || exit 1
+
+# Initialize database and start application
+CMD python backend/create_db.py && \
+    uvicorn backend.app.main:app \
+    --host 0.0.0.0 \
+    --port 7860 \
+    --log-level info