Dockerize repo, create Dockerfile, docker-compose.yml and update README.md (#17)

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Dockerfile

@@ -0,0 +1,28 @@
+# Use Node.js 20 as the base image
+FROM node:20
+
+# Set the working directory
+WORKDIR /app
+
+# Copy package.json and package-lock.json
+COPY package*.json ./
+
+# Install dependencies
+RUN npm install
+
+# Copy the application code
+COPY . .
+
+# Set environment variables
+ENV GEMINI_API_KEY=${GEMINI_API_KEY}
+ENV JINA_API_KEY=${JINA_API_KEY}
+ENV BRAVE_API_KEY=${BRAVE_API_KEY}
+
+# Build the application
+RUN npm run build
+
+# Expose the port the app runs on
+EXPOSE 3000
+
+# Set the default command to run the application
+CMD ["npm", "run", "serve"]