Adds frontend/public/logo.svg as a placeholder (rendered at /build/logo.svg
after Vite build). Email template share_notification.html.twig swaps the
text "WeVisto" header for an <img> referencing /build/logo.svg via
absolute_url, so dropping in the final design swaps one file with no
template change.
bin/smoke.sh HOST now defaults to wevisto.com — legacy host still smoke-
testable via HOST=pictureframe.edholm.me bin/smoke.sh under the dual-
domain coexistence (Option C).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
