Richer page previews for vendor links

We added dynamic page preview cards for vendor links so shared Huntertech.io URLs look better in iMessage, X, Slack, and other social platforms. When a supported vendor route is shared, Huntertech.io can now render a 1200x630 preview image for that specific vendor and section.

The new preview card highlights the vendor favicon, logo-derived color palette, website, a concise vendor description, and the available capabilities for that vendor. The active route is emphasized in the badge row, so overview, incidents, maintenance, advisories, updates, press releases, and compliance links can each feel specific in previews.

This gives us a reusable standard for future page previews. Instead of creating static images by hand, the card is rendered from structured vendor data, cached, and served through the same preview pipeline used by the Updates page.