Replace Astro/Strapi site with Next.js static export

- Fresh structure: Next.js App Router + Tailwind v4 at the repo root, exported
  as static files (output: export) and served by static-web-server
- Remove the Strapi CMS, Astro app, Pagefind search, comments, old scripts,
  Lighthouse config and compose files; content in content/ is now plain
  markdown with YAML frontmatter
- Pages: About, Writing, Reading (3D bookshelf) and Portfolio, styled after
  adammaj.com
- SEO: metadata and canonicals, JSON-LD, generated OG images, sitemap, robots,
  RSS and JSON feeds, llms.txt
- Umami via PUBLIC_UMAMI_SCRIPT_URL / PUBLIC_UMAMI_WEBSITE_ID (build args)
- Dockerfile builds the export and serves it with sws.toml (security headers,
  clean URLs, .well-known, OG image content type, immutable asset caching)
- Prettier and cspell for content with a husky/lint-staged pre-commit hook
- Old redirect list dropped to start from a clean slate

src/components/JsonLd.tsx

@@ -0,0 +1,29 @@
+/** Renders a JSON-LD block. `<` is escaped so content can't close the script tag. */
+export function JsonLd({
+  data,
+}: {
+  data: Record<string, unknown> | Record<string, unknown>[];
+}) {
+  return (
+    <script
+      type="application/ld+json"
+      // biome-ignore lint/security/noDangerouslySetInnerHtml: JSON-LD must be inlined; `<` is escaped
+      dangerouslySetInnerHTML={{
+        __html: JSON.stringify(data).replace(/</g, "\\u003c"),
+      }}
+    />
+  );
+}
+
+export function breadcrumbs(items: { name: string; url: string }[]) {
+  return {
+    "@context": "https://schema.org",
+    "@type": "BreadcrumbList",
+    itemListElement: items.map((item, i) => ({
+      "@type": "ListItem",
+      position: i + 1,
+      name: item.name,
+      item: item.url,
+    })),
+  };
+}