Migrate validate links script from next-site and setup GitHub action (#…

…51365)

This PR migrates and adapts the [validate docs links script from `next-site`](vercel/front#23185). This script is triggered by a GitHub action whenever a file in the `/docs` folder is updated. If broken links are found in the docs, the check fails and we post a comment on the PR with a list of broken links.

Co-authored-by: Michael Novotny <446260+manovotny@users.noreply.github.com>

.eslintignore

@@ -22,6 +22,7 @@ packages/react-dev-overlay/lib/**
 .github/actions/next-stats-action/.work
 .github/actions/issue-validator/index.mjs
 .github/actions/issue-labeler/lib/index.js
+.github/actions/validate-docs-links/lib/index.js
 packages/next-codemod/transforms/__testfixtures__/**/*
 packages/next-codemod/transforms/__tests__/**/*
 packages/next-codemod/**/*.js

.github/actions/validate-docs-links/README.MD

@@ -0,0 +1,17 @@
+# GitHub Action for Validating Documentation Links
+
+This action ensures that internal links in `.mdx` files in the `/docs/` directory are valid. It runs on every pull request that includes changes to these files.
+
+The action is triggered by the workflow defined in `.github/workflows/validate-docs-links.yml`.
+
+## Usage
+
+This action is written in TypeScript and compiled locally before being pushed to GitHub.
+
+To make changes:
+
+- Edit the `src/index.ts` file.
+- Navigate to the script folder `cd .github/actions/validate-docs-links`
+- Run `npm install` to install dependencies.
+- Run `npm run build` to compile code. This will create an updated `lib/index.js`.
+- Commit and push changes to GitHub.

.github/actions/validate-docs-links/lib/package.json

@@ -0,0 +1,3 @@
+{
+  "type": "module"
+}

.github/actions/validate-docs-links/package.json

@@ -0,0 +1,26 @@
+{
+  "private": true,
+  "type": "module",
+  "exports": "./lib/index.js",
+  "files": [
+    "src"
+  ],
+  "scripts": {
+    "build": "npm run types && ncc -m -o ./lib build src/index.ts --license licenses.txt",
+    "types": "tsc"
+  },
+  "devDependencies": {
+    "@types/github-slugger": "^1.3.0",
+    "@vercel/ncc": "0.34.0"
+  },
+  "dependencies": {
+    "@actions/github": "^5.1.1",
+    "github-slugger": "1.2.0",
+    "gray-matter": "4.0.2",
+    "rehype-raw": "4.0.1",
+    "remark-parse": "7.0.1",
+    "remark-rehype": "5.0.0",
+    "unified": "8.4.1",
+    "unist-util-visit": "2.0.0"
+  }
+}