Bring the tighten-ui brand treatment into new-ui:
- Replace the emoji book (📚) in the sidebar header with the book-open
icon rendered in the theme accent color, matching the tighten-ui
header brand (templates/header.templ).
- Add web/static/favicon.svg (book-open glyph, tokyo-night accent
#7aa2f7 stroke) and reference it from the <head> of all 27 page
templates, so the favicon is present on login/setup/error pages too.
- Regenerate templ output for all affected templates.
Add standalone error page template for graceful error display when the
main app fails. Includes inline CSS since error pages must work when
CSS fails to load. Add error toast component for displaying errors.
john-okeefe