fix: wrap nav data in items key for Decap CMS compatibility

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

site/data/nav.yml

@@ -1,23 +1,24 @@
-- name: Home
-  url: /
-  weight: 1
+items:
+  - name: Home
+    url: /
+    weight: 1
 
-- name: Docs
-  url: /docs/
-  weight: 2
+  - name: Docs
+    url: /docs/
+    weight: 2
 
-- name: Notes
-  url: /notes/
-  weight: 3
+  - name: Notes
+    url: /notes/
+    weight: 3
 
-- name: Essays
-  url: /essays/
-  weight: 4
+  - name: Essays
+    url: /essays/
+    weight: 4
 
-- name: Articles
-  url: /articles/
-  weight: 5
+  - name: Articles
+    url: /articles/
+    weight: 5
 
-- name: Tags
-  url: /tags/
-  weight: 6
+  - name: Tags
+    url: /tags/
+    weight: 6

site/layouts/partials/nav.html

@@ -1,7 +1,7 @@
 <nav>
   <ul><li><a href="/"><strong>{{ .Site.Title }}</strong></a></li></ul>
   <ul>
-    {{- range sort hugo.Data.nav "weight" }}
+    {{- range sort hugo.Data.nav.items "weight" }}
     <li><a href="{{ .url }}"{{ if eq (relURL .url) $.RelPermalink }} aria-current="page"{{ end }}>{{ .name }}</a></li>
     {{- end }}
   </ul>