Add the Marble and Highlighter templates, completing the 13 reference templates

Marble uses a flat-to-gradient band in place of the marble photo and bundles Lustria (OFL).
Both logo slots are opt-in. Quirk 13 documents a fontkit glyph-cache issue that the
tests work around with warm-up renders; the engine fix follows separately.

src/pdf/templates/catalog.ts

@@ -36,6 +36,8 @@ export const TEMPLATE_CATALOG: readonly TemplateCatalogEntry[] = [
   { id: "citrus-split", name: "Citrus Split", family: "northline", thumbnail: "/templates/citrus-split.png" },
   { id: "monolith", name: "Monolith", family: "standalone", thumbnail: "/templates/monolith.png" },
   { id: "cobalt-stripe", name: "Cobalt Stripe", family: "standalone", thumbnail: "/templates/cobalt-stripe.png" },
+  { id: "marble", name: "Marble", family: "standalone", thumbnail: "/templates/marble.png", logoOptIn: true },
+  { id: "highlighter", name: "Highlighter", family: "standalone", thumbnail: "/templates/highlighter.png", logoOptIn: true },
 ];
 
 /** The entry for an id; an unknown id falls back to Classic, like getTemplate. */