Add Dockerfile

DOCKER.md

@@ -0,0 +1,7 @@
+```
+docker build -t pythagora .
+
+docker run -v /Volumes/src/jellyfin-web:/data -it pythagora npx pythagora \
+  --unit-tests \
+  --path /data/src/controllers/list.js
+```

Dockerfile

@@ -0,0 +1,18 @@
+FROM node:18
+
+# Create app directory
+RUN mkdir /app
+
+# Set working directory
+WORKDIR /app
+
+# Copy package.json and package-lock.json
+COPY package*.json ./
+
+# Install dependencies
+RUN npm i -g pythagora
+
+# Copy source code
+COPY . .
+
+VOLUME [ "/data" ]