Layout components now self-resolve context (cart-mini, auth-menu, nav-tree,
rights, URLs) via new IO primitives (root-header-ctx, select-colours,
account-nav-ctx, app-rights) and defmacro wrappers (~root-header-auto,
~auth-header-row-auto, ~root-mobile-auto). This eliminates _ctx_to_env(),
HELPER_CSS_CLASSES, and verbose :key threading across all 10 services.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Move ~1670 lines to 6 sub-modules: renders.py, layouts.py, helpers.py,
cards.py, filters.py, utils.py. Update all bp route imports.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
