fix(seo): exclude noindex aviso-legal page from sitemap; add full audit report

Sitemap filter was excluding cookies/ and privacidad/ but not
aviso-legal/, even though that page is marked noindex,follow -- a
noindexed page has no business being listed for crawl discovery.

Also adds docs/seo-audit/mnqcatering.com-audit/ -- the full multi-agent
SEO audit run this session against the corrected live domain
(www.mnqeventos.es), including the FULL-AUDIT-REPORT.md, ACTION-PLAN.md,
and per-category findings files.

astro.config.mjs

@@ -10,7 +10,10 @@ export default defineConfig({
   }),
   integrations: [
     sitemap({
-      filter: (page) => !page.endsWith('/cookies/') && !page.endsWith('/privacidad/'),
+      filter: (page) =>
+        !page.endsWith('/cookies/') &&
+        !page.endsWith('/privacidad/') &&
+        !page.endsWith('/aviso-legal/'),
     }),
   ],
 });