Add lychee workflow to check links in MD files

.github/workflows/lychee.yml

@@ -0,0 +1,32 @@
+name: Check Links
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+    branches:
+      - main
+  schedule:
+    # Run weekly on Monday at 00:00 UTC
+    - cron: '0 0 * * 1'
+  workflow_dispatch:
+
+jobs:
+  check-links:
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Link Checker
+        uses: lycheeverse/lychee-action@v2
+        with:
+          # Check all markdown files in the repository
+          args: --verbose --no-progress --max-retries 3 --accept=200,204,429 '**/*.md'
+          # Fail action on broken links
+          fail: true
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}