Point docs to Astral favicon (#13219)

## Summary

Same as https://github.com/astral-sh/uv/pull/6951. Unfortunately we have
to use a single favicon for the docs.

.github/workflows/publish-docs.yml

@@ -34,10 +34,10 @@ jobs:
       - name: "Set docs version"
         run: |
           version="${{ (inputs.plan != '' && fromJson(inputs.plan).announcement_tag) || inputs.ref }}"
-          # if version is missing, exit with error
-          if [[ -z "$version" ]]; then
-          echo "Can't build docs without a version."
-          exit 1
+          # if version is missing, use 'latest'
+          if [ -z "$version" ]; then
+            echo "Using 'latest' as version"
+            version="latest"
           fi
 
           # Use version as display name for now
@@ -145,6 +145,7 @@ jobs:
           GITHUB_TOKEN: ${{ secrets.ASTRAL_DOCS_PAT }}
         run: |
           branch_name="${{ env.branch_name }}"
+
           # auto-merge the PR if the build was triggered by a release. Manual builds should be reviewed by a human.
           # give the PR a few seconds to be created before trying to auto-merge it
           sleep 10

docs/.overrides/main.html

@@ -0,0 +1,20 @@
+{% extends "base.html" %}
+
+{% block extrahead %}
+<link rel="apple-touch-icon" sizes="180x180" href="/static/apple-touch-icon.png"/>
+<link rel="icon" type="image/png" sizes="32x32" href="/static/favicon-32x32.png"/>
+<link rel="icon" type="image/png" sizes="16x16" href="/static/favicon-16x16.png"/>
+<link rel="manifest" href="/static/site.webmanifest"/>
+<link rel="mask-icon" href="/static/safari-pinned-tab.svg" color="#2e183d"/>
+<meta name="msapplication-TileColor" content="#d7ff64"/>
+<meta name="theme-color" content="#ffffff"/>
+<meta name="robots" content="index,follow"/>
+<script type="application/ld+json">
+    {
+        "@context": "https://schema.org",
+        "@type": "WebSite",
+        "name": "Astral",
+        "url": "https://astral.sh"
+    }
+</script>
+{% endblock %}

mkdocs.template.yml

@@ -2,7 +2,7 @@ site_name: Ruff
 theme:
   name: material
   logo: assets/bolt.svg
-  favicon: assets/ruff-favicon.png
+  favicon: assets/favicon.ico
   features:
     - navigation.instant
     - navigation.instant.prefetch