Generate share images

Without cards, a page's og:image is its own seo.image, or else the site's ogImage from the site settings.

Draw cards for detail pages

1. In the CMS's site settings, turn on share cards, or set og.enabled in src/content/settings/site.md.

   og:
     enabled: true
     types:
       boats:
         enabled: true
         style: bold
         headlineField: title
         sublineField: price

2. Turn on a type for each collection that should get cards: towns, services, or a listing's id (the blog is posts).

3. Build. Each entry of an enabled type gets /og/<path>.png, and its page's og:image, og:image:width and og:image:height point at it.

With cards on, a page without a card or its own seo.image falls back to the site's ogImage, then the home page's first hero image, then /og/default.png, a card the build draws with the site's name.

Key	Default	What it sets
og.enabled	false	draws cards at all
og.types.<type>.enabled	false	cards for that collection
og.types.<type>.style	editorial	editorial, bold or ops
og.types.<type>.headlineField	the title, or the name for towns	the field shown large, or business for the site's name
og.types.<type>.sublineField	none, or price for a catalog	the field shown under it, or none
og.types.<type>.scrim	55	how much the entry's image is darkened behind the text, 0 to 100
og.types.<type>.showLogo	true	the site's wordmark on the card
og.types.<type>.accent	the brand colour	the card's accent colour

The card's background is the entry's cover, its first gallery image, or its hero or media image, and the brand colour when it has none. An entry's own seo.image replaces its card, and seo.ogRaw: true uses the entry's image as it is, without drawing on it.

The fields a type offers: title, date and excerpt for articles; title, price, status, category and date for catalogs; name, title and heroSubtitle for towns; title, navLabel and summary for services.