add comments explaining npm vs pnpm for remark-mdx global install

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: s-sajid-ali

.github/workflows/lint.yaml

@@ -27,6 +27,14 @@ jobs:
         with:
           version: latest
 
+      # npm (not pnpm) is intentional: remark-cli is installed globally by the
+      # action at /usr/local/lib/node_modules/. pnpm's global store is not on
+      # that resolution path, so remark-cli would fall back to resolving
+      # remark-mdx from the project's node_modules, where @mdx-js/react pulls
+      # in mdast-util-mdx-jsx@3 — incompatible with remark-cli@10's bundled
+      # unified v10 stack. npm -g puts remark-mdx@2 next to remark-cli so the
+      # versions stay compatible. install_deps: false prevents the action from
+      # running npm install and reintroducing the incompatible project deps.
       - name: Install remark-mdx globally
         run: npm install -g remark-mdx@2