Pin Docker image to exact npm version via build arg (#353)

Pin Docker image to exact npm version via build arg

Author: kvz

.github/workflows/docker-mcp.yml

@@ -45,6 +45,8 @@ jobs:
         with:
           context: packages/mcp-server
           file: packages/mcp-server/Dockerfile
+          build-args: |
+            MCP_VERSION=${{ steps.version.outputs.version }}
           push: true
           tags: |
             ghcr.io/transloadit/mcp-server:${{ steps.version.outputs.version }}

packages/mcp-server/Dockerfile

@@ -1,4 +1,5 @@
 FROM node:22-alpine
-RUN npm install -g @transloadit/mcp-server@latest
+ARG MCP_VERSION=latest
+RUN npm install -g @transloadit/mcp-server@${MCP_VERSION}
 USER node
 ENTRYPOINT ["transloadit-mcp", "stdio"]