fix: add GA gtag.js snippet to head for Search Console verification

Injects the raw Google Analytics snippet via theme override so Google
Search Console can verify site ownership. Removes the duplicate
Material built-in analytics config.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

mkdocs.yml

@@ -69,9 +69,6 @@ extra:
     - icon: fontawesome/brands/medium
       link: https://alirezarezvani.medium.com
       name: Medium
-  analytics:
-    provider: google
-    property: G-VHRY2VKY9K
   generator: false
 
 extra_css: