Resolve share URLs from the instance host and ship 1200×630 Open Graph images.

Staging no longer advertises production canonicals, and Slack/social previews get a default hero card with template and article overrides.

Co-authored-by: Cursor <cursoragent@cursor.com>

lib/assetUtils.ts

@@ -153,6 +153,11 @@ export function contentBlogHorizontalPath(slug: string): string {
   return `/content/blog/${slug}-horizontal.svg`;
 }
 
+/** 1200×630 social preview rasterized from the article's section banner. */
+export function contentBlogOgPath(slug: string): string {
+  return `/content/blog/${slug}-og.png`;
+}
+
 /** Wide banner background for ContentBanner at md+ (Figma Section, 1920×672). */
 export function contentBlogSectionPath(slug: string): string {
   return `/content/blog/${slug}-section.svg`;
@@ -250,6 +255,10 @@ export const ASSETS = {
 
   // Marketing
   HERO_IMAGE: "assets/marketing/hero-image.png",
+  /** Default 1200×630 Open Graph image (hero crop). */
+  OG_IMAGE: "assets/marketing/og-image.png",
+  /** Templates-index 1200×630 Open Graph image. */
+  OG_IMAGE_TEMPLATES: "assets/marketing/og-image-templates.png",
 
   // Top nav union ornaments
   UNION_XSM: "assets/shapes/union-xsm.svg",