Account nav links and page panels (tickets, bookings) now fetched
as HTML fragments from events app instead of using widget registry.
All three widget registration functions are now no-ops.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Templates now consume container_nav_html and card_widgets_html from
fragment fetches instead of iterating widgets.container_nav / container_cards.
OOB nav template renders entry/calendar links directly from data.
Calendar and market widget registrations removed (account widgets remain).
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Introduces a widget system where domains register UI fragments into
named slots (container_nav, container_card, account_page, account_link).
Host apps iterate widgets generically without naming any domain.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>