Add a hero image (rendered from the redesigned PDF's own cover) so the
opt-in page shows the actual resource instead of pure text, and make
the post-submit message PDF-specific with a working /gift-thanks
fallback link instead of a generic dead-end "check your inbox" line.
Both are opt-in per-page params (hero_image, success_message) so the
real drip-course page's rendering is unchanged.
Matches the gift.<domain> vanity redirect's own name instead of a
different word for the same page.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
will