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

Dockerfile

@@ -1,20 +1,30 @@
-# Production image for the Astro site. Build from the workspace root:
-#   docker build -t andwati-site .
+# syntax=docker/dockerfile:1
+# Static site: build with Next (output: export), serve with static-web-server.
+#   docker build -t andwati-site \
+#     --build-arg PUBLIC_UMAMI_SCRIPT_URL=... --build-arg PUBLIC_UMAMI_WEBSITE_ID=... .
 
-FROM node:24-bookworm-slim AS build
+FROM node:24-alpine AS deps
+ENV PNPM_HOME=/pnpm PATH=/pnpm:$PATH
 RUN corepack enable
 WORKDIR /app
+COPY package.json pnpm-lock.yaml pnpm-workspace.yaml ./
+RUN --mount=type=cache,id=pnpm,target=/pnpm/store \
+    pnpm install --frozen-lockfile
 
-COPY pnpm-workspace.yaml pnpm-lock.yaml package.json ./
-COPY apps/site/package.json apps/site/package.json
-COPY apps/cms/package.json apps/cms/package.json
-COPY apps/site apps/site
-COPY content content
-COPY scripts scripts
-RUN pnpm install --frozen-lockfile --filter andwati-com --filter site
-RUN pnpm --filter site build
+FROM node:24-alpine AS build
+ENV PNPM_HOME=/pnpm PATH=/pnpm:$PATH NEXT_TELEMETRY_DISABLED=1
+RUN corepack enable
+WORKDIR /app
+COPY --from=deps /app/node_modules ./node_modules
+COPY . .
+# Umami is read at build time (pages are prerendered), so pass these as build args.
+ARG PUBLIC_UMAMI_SCRIPT_URL
+ARG PUBLIC_UMAMI_WEBSITE_ID
+ENV PUBLIC_UMAMI_SCRIPT_URL=$PUBLIC_UMAMI_SCRIPT_URL \
+    PUBLIC_UMAMI_WEBSITE_ID=$PUBLIC_UMAMI_WEBSITE_ID
+RUN pnpm build
 
 FROM ghcr.io/static-web-server/static-web-server:2
-COPY --from=build /app/apps/site/dist /public
+COPY --from=build /app/out /public
 COPY sws.toml /sws.toml
 EXPOSE 80