Fix astro upstream org name (withastro, not astro-build)

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

Author: codegraphtheory

repos.yaml

@@ -134,7 +134,7 @@ categories:
         pill: "UI"
         pill_class: "pill-blue"
       - name: astro
-        upstream: astro-build/astro
+        upstream: withastro/astro
         description: "The web framework for content-driven websites"
         pill: "Meta-framework"
         pill_class: "pill-accent"