blog_url, market_url, cart_url, events_url and g.rights were only
available as Jinja globals, not in the ctx dict passed to sexp
helper functions. This caused all cross-service links in the header
system (post title, cart badge, admin cog, admin nav items) to
produce relative URLs resolving to the current service domain.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>