fix: drop noindex from category redirect stubs

Redirect stubs for renamed category URLs carried a robots noindex meta, so Search Console filed them under "Excluded by 'noindex' tag" instead of treating the instant meta refresh as a permanent redirect, and the old URLs' ranking was not passed to the new pages.

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

website/templates/redirect.html

@@ -5,7 +5,6 @@
 <link rel="canonical" href="{{ target_url }}">
 <script>location="{{ target_url }}"</script>
 <meta http-equiv="refresh" content="0; url={{ target_url }}">
-<meta name="robots" content="noindex">
 <h1>Redirecting&hellip;</h1>
 <a href="{{ target_url }}">Click here if you are not redirected.</a>
 </html>

website/tests/test_build.py

@@ -1083,7 +1083,7 @@ class TestBuild:
         stub = (site / "categories" / "old-widgets" / "index.html").read_text(encoding="utf-8")
         assert '<link rel="canonical" href="https://awesome-python.com/categories/widgets/">' in stub
         assert '<meta http-equiv="refresh" content="0; url=https://awesome-python.com/categories/widgets/">' in stub
-        assert '<meta name="robots" content="noindex">' in stub
+        assert "noindex" not in stub
         assert "old-widgets" not in (site / "sitemap.xml").read_text(encoding="utf-8")
 
     def test_build_renders_category_intro_and_uses_lead_as_meta_description(self, tmp_path):