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

content/portfolio/example-project.md

@@ -1,15 +1,11 @@
-+++
-title = "Example Project"
-description = "Placeholder portfolio entry establishing the schema."
-role = "Author"
-date_start = 2026-01-01
-outcome = "Established the portfolio content schema."
-draft = false
-[[links]]
-label = "Source"
-url = "https://github.com/andwati"
-[taxonomies]
-tags = ["placeholder"]
-+++
-
-Placeholder case study body establishing the `portfolio` content schema.
+---
+title: "Example Project"
+description: "Placeholder portfolio entry establishing the schema."
+role: "Author"
+dateStart: "2026-01-01"
+outcome: "Established the portfolio content schema."
+links:
+  - label: "Source"
+    url: "https://github.com/andwati"
+tags: ["placeholder"]
+---