feat: add Docker support with Dockerfile and docker-compose.yml, update asset upload to use backend URL

Dockerfile

@@ -0,0 +1,43 @@
+# Build stage
+FROM node:20-alpine AS builder
+
+WORKDIR /app
+
+# Copy package files
+COPY package*.json ./
+
+# Install dependencies with clean cache
+RUN npm ci --prefer-offline --no-audit
+
+# Copy source code
+COPY . .
+
+# Build the application
+RUN npm run build
+
+# Production stage
+FROM node:20-alpine
+
+WORKDIR /app
+
+# Copy package files
+COPY package*.json ./
+
+# Install only production dependencies with clean cache
+RUN npm ci --prefer-offline --no-audit --omit=dev
+
+# Copy built application from builder stage
+COPY --from=builder /app/.output ./.output
+
+# Expose port
+EXPOSE 3000
+
+# Set environment to production
+ENV NODE_ENV=production
+
+# Health check
+HEALTHCHECK --interval=30s --timeout=10s --start-period=40s --retries=3 \
+  CMD node -e "require('http').get('http://localhost:3000/', (r) => {process.exit(r.statusCode === 200 ? 0 : 1)})"
+
+# Start the application
+CMD ["node", ".output/server/index.mjs"]