Fix extend and contribute navigation

Author: theletterf

extend/contribute/api-docs/overview.md

@@ -3,7 +3,7 @@
 This page explains at a high-level how API docs work at Elastic today, with context on how this differs from our previous approaches and where we're heading. Use this page to understand the core primitives and workflows that apply across all Elastic teams, so you can contribute effectively.
 
 :::{tip}
-The API docs use a different system to the main Elastic docs. Refer to [Contribute to Elastic docs](../../contribute/index.md) for an overview of the two systems.
+The API docs use a different system to the main Elastic docs. Refer to [Contribute to Elastic docs](/extend/contribute/index.md) for an overview of the two systems.
 :::
 
 While the implementation details [vary significantly across teams](workflows.md), at a high level:

extend/contribute/toc.yml

@@ -0,0 +1,11 @@
+project: 'Contribute'
+toc:
+  - file: api-docs/index.md
+    children:
+      - file: api-docs/overview.md
+      - file: api-docs/checklist.md
+      - file: api-docs/guidelines.md
+      - file: api-docs/organize-annotate.md
+      - file: api-docs/quickstart.md
+      - file: api-docs/workflows.md
+      - file: api-docs/help.md

extend/index.md

@@ -1,12 +1,17 @@
-# Extend and contribute
+---
+navigation_title: Extend and contribute
+description: Extend and contribute to Elastic
+---
+
+# Extend and contribute to Elastic
 
 This section contains information on how to extend or contribute to our various products.
 
 ## Contributing to Elastic documentation
 
 You can contribute to the Elastic documentation in several ways.
 
-Refer to [Contribute to Elastic documentation](./contribute/index.md) for an overview.
+Refer to [Contribute to Elastic documentation](/extend/contribute/index.md) for an overview.
 
 ## Contributing to Elastic Projects
 

extend/toc.yml

@@ -1,14 +1,4 @@
+project: 'Extend'
 toc:
   - file: index.md
-    children:
-      - file: contribute/index.md
-        children:
-          - file: contribute/api-docs/index.md
-            children:
-              - file: contribute/api-docs/overview.md
-              - file: contribute/api-docs/checklist.md
-              - file: contribute/api-docs/guidelines.md
-              - file: contribute/api-docs/organize-annotate.md
-              - file: contribute/api-docs/quickstart.md
-              - file: contribute/api-docs/workflows.md
-              - file: contribute/api-docs/help.md
+  - toc: contribute