feat: share image, metadata and icons that match the new site

The link preview used an old template with a blog description. The share
image is now a screenshot of the real hero (scripts/render-share-image.mjs),
served as Open Graph and Twitter image. Title and description come from one
place and are used by the page, the previews and the structured data. Adds an
apple touch icon and removes the old share-image template and its fonts.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

apps/web/src/content/site.ts

@@ -3,6 +3,12 @@ import { parseEmailParts, type EmailParts } from "@/src/domain/email";
 export const SITE_NAME = "Marc Mintel";
 export const SITE_URL = "https://mintel.me";
 
+/** One wording for the browser title, search results and link previews. */
+export const SITE_TITLE =
+  "Marc Mintel — Freelance developer for web apps and websites";
+export const SITE_DESCRIPTION =
+  "Freelance developer with 15 years of experience. I build web apps, interfaces and websites, and automate processes between your systems.";
+
 // The contact address, kept in parts on purpose: the complete address must never
 // appear as one string in the page source (see src/components/EmailLink.tsx).
 const parsedEmail = parseEmailParts({