fix: remove Jekyll workflow and harden MkDocs deploy

.github/workflows/docs.yml

@@ -17,6 +17,13 @@ on:
       - 'mkdocs.yml'
       - '.github/workflows/docs.yml'
 
+permissions:
+  contents: read
+
+concurrency:
+  group: "pages"
+  cancel-in-progress: false
+
 jobs:
   build:
     runs-on: ubuntu-latest
@@ -26,13 +33,20 @@ jobs:
 
       - name: Set up Python
         uses: actions/setup-python@v5
+        with:
+          python-version: '3.12'
 
       - name: Install dependencies
         run: pip install mkdocs mkdocs-material
 
       - name: Build site
         run: mkdocs build
 
+      - name: Upload Pages artifact
+        uses: actions/upload-pages-artifact@v3
+        with:
+          path: site
+
   deploy:
     if: github.event_name == 'push' && github.ref == 'refs/heads/main'
     needs: build
@@ -44,18 +58,6 @@ jobs:
       name: github-pages
       url: ${{ steps.deployment.outputs.page_url }}
     steps:
-      - name: Checkout repository
-        uses: actions/checkout@v4
-
-      - name: Set up Python
-        uses: actions/setup-python@v5
-
-      - name: Install dependencies
-        run: pip install mkdocs mkdocs-material
-
-      - name: Build site
-        run: mkdocs build
-
       - name: Deploy to GitHub Pages
         id: deployment
         uses: actions/deploy-pages@v4