Move link check to a job dependent on build

Author: JimMadge

.github/workflows/build-website.yml

@@ -21,3 +21,33 @@ jobs:
       - name: Build website
         run: |
           npm run build
+      - name: Upload html output as artifact
+        uses: actions/upload-artifact@330a01c490aca151604b8cf639adc76d48f6c5d4 # v5.0.0
+        with:
+          name: html-${{ github.run_id }}
+          path: ./dist
+  link_check:
+    runs-on: ubuntu-latest
+    needs: build
+    steps:
+      - name: Checkout lychee config file from repository
+        uses: actions/checkout@v5
+        with:
+          sparse-checkout: |
+            lychee.toml
+          sparse-checkout-cone-mode: false
+      - name: Ensure destination folder exists
+        run: |
+          mkdir ./dist
+      - name: Download html files from artifact
+        uses: actions/download-artifact@018cc2cf5baa6db3ef3c5f8a56943fffe632ef53 # v6.0.0
+        with:
+          name: book-html-${{ github.run_id }}
+          path: ./dist
+      - name: Offline link check
+        uses: lycheeverse/lychee-action@v2
+        with:
+          # Only check local files, no network requests
+          args: --config './lychee.toml' --no-progress --offline --root-dir "$GITHUB_WORKSPACE/dist/" dist/**/*.html
+          # Fail job when lychee returns a non-zero exit code
+          fail: true