ci: add PR preview deployments

.github/workflows/pr-preview.yml

@@ -0,0 +1,41 @@
+name: PR Preview Deploy
+
+on:
+  pull_request:
+    types: [opened, synchronize, reopened, closed]
+
+concurrency:
+  group: preview-${{ github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  deploy-preview:
+    runs-on: ubuntu-latest
+    permissions:
+      contents: write
+      pull-requests: write
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Set up Python
+        uses: actions/setup-python@v5
+        with:
+          python-version: '3.12'
+
+      - name: Install dependencies
+        run: |
+          python -m pip install --upgrade pip
+          pip install mkdocs mkdocs-material mkdocs-video mkdocs-redirects
+
+      - name: Build MkDocs site
+        if: github.event.action != 'closed'
+        run: mkdocs build
+
+      - name: Deploy PR Preview
+        uses: rossjrw/pr-preview-action@v1
+        with:
+          source-dir: ./site/
+          preview-branch: gh-pages
+          umbrella-dir: pr-preview
+          action: auto