Add npm install step to docker

Dockerfile

@@ -0,0 +1,40 @@
+# Stage 1: Build and install Node.js dependencies
+FROM node:18-alpine as nodebuilder
+
+# Set working directory
+WORKDIR /app
+
+# Copy package.json and package-lock.json (or yarn.lock if you use Yarn)
+COPY app/package.json app/package-lock.json ./
+
+# Install dependencies
+RUN npm install
+
+# Optionally, if your application needs to be built:
+# COPY app/ ./
+# RUN npm run build
+
+# Stage 2: Setup the final image with Jekyll and Node.js environment
+FROM tiryoh/jekyll:4.2.1
+
+# Copy Node.js build artifacts from the previous stage
+COPY --from=nodebuilder /app/node_modules /srv/jekyll/node_modules
+
+# Copy your application code, if there's anything to run directly
+# COPY --from=nodebuilder /app /srv/jekyll
+
+# Set the working directory
+WORKDIR /srv/jekyll
+
+# Add Node.js and npm to PATH
+ENV PATH="/srv/jekyll/node_modules/.bin:${PATH}"
+
+# Continue setting up your Jekyll environment
+# For example, copy over your Jekyll site files
+# COPY . /srv/jekyll
+
+# Expose the port Jekyll will run on
+EXPOSE 8080
+
+# Command to run your Jekyll site
+CMD ["jekyll", "build", "--watch"]