Two critical fixes for POC site rendering:
1. Storefront content page route now selects template based on
page.template field: 'full' → landing-full.html (section-based),
'modern'/'minimal' → their respective templates. Default stays
content-page.html (plain HTML). Previously always used content-page
which ignores page.sections JSON.
2. Storefront base_url uses store.subdomain (lowercase, hyphens)
instead of store.store_code (uppercase, underscores) for URL
building. Nav links now point to correct paths that the store
context middleware can resolve.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>