fix: resolve search dropdown clickability and add new documentation pages

- Fix: resolve search dropdown clickability by increasing z-index. The DocSearch button and dropdown were not clickable due to z-index conflict with sticky sidebar elements. Added position: relative and z-index: 501 to .docsearch .DocSearch-Button, and z-index: 500 to .docsearch wrapper to ensure proper stacking context.

- Docs: add UI Standards documentation for developer guidelines
- Docs: add Routing documentation for developer reference
- Docs: add Affiliates documentation for marketing section

docu.json

@@ -122,6 +122,10 @@
         {
           "title": "Wishlist",
           "href": "/wishlist"
+        },
+        {
+          "title": "Affiliates",
+          "href": "/affiliates"
         }
       ]
     },
@@ -239,6 +243,14 @@
           "title": "Store Owner",
           "href": "/store-owner"
         },
+        {
+          "title": "UI Standards",
+          "href": "/ui-standards"
+        },
+        {
+          "title": "Routing",
+          "href": "/routing"
+        },
         {
           "title": "Software Updates",
           "href": "/software-updates"