fix(seo): pre-GSC audit — sitemap, redirects, OG tags, schema markup
- sitemap: replace /market-score with /padelnomics-score, add /opportunity-map,
remove /billing/pricing (blocked by robots.txt), deduplicate articles query
- app: fix /market-score redirect chain (→ /en/padelnomics-score directly)
- base.html: move default OG tags inside {% block head %} so child overrides
replace them instead of duplicating
- features, planner, directory: add JSON-LD WebPage + BreadcrumbList schema
- export pages: add meta descriptions and {% block head %} where missing
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>