feat: core layouts and partials (Phase 3)

- baseof.html with named blocks (head_extra, body_class, main, scripts)
- single.html with data-pagefind-body wrapper
- list.html using post-card partial
- home.html placeholder (Phase 4 fills hero/projects/recent-posts)
- 404.html with vi i18n
- _partials: head (full meta + OG + Twitter Card + RSS autodiscovery + theme-flash script), header, nav, footer, meta, post-card, icon
- Sample post fixture in exampleSite to validate render

ci: bump GitHub Actions to Node 24-compatible versions

- actions/checkout v4 → v6
- actions/setup-node v4 → v6, node 20 → 22
- actions/upload-pages-artifact v3 → v5
- actions/deploy-pages v4 → v5

.github/workflows/pages.yml

@@ -20,7 +20,7 @@ jobs:
     env:
       HUGO_VERSION: 0.154.0
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
         with:
           submodules: recursive
           fetch-depth: 0
@@ -32,9 +32,9 @@ jobs:
           extended: true
 
       - name: Setup Node
-        uses: actions/setup-node@v4
+        uses: actions/setup-node@v6
         with:
-          node-version: 20
+          node-version: 22
           cache: npm
 
       - name: Install dependencies
@@ -53,7 +53,7 @@ jobs:
           fi
 
       - name: Upload artifact
-        uses: actions/upload-pages-artifact@v3
+        uses: actions/upload-pages-artifact@v5
         with:
           path: exampleSite/public
 
@@ -65,4 +65,4 @@ jobs:
       url: ${{ steps.deployment.outputs.page_url }}
     steps:
       - id: deployment
-        uses: actions/deploy-pages@v4
+        uses: actions/deploy-pages@v5