chore: retire site, redirect www.millerdatabases.com to danielmiller.ca

[daniel-miller]

Summary

• Site being retired. All 14 posts migrated to https://medium.com/@daniel-miller
• Replaces Astro build output with a static redirect page targeting https://danielmiller.ca/
• 404.html mirrors index.html so any deep-link path (e.g. /the-copilot-delusion/) also redirects
• Deploy workflow drops node/npm/build steps, uploads redirect/ directory instead of dist/

Changes

• Add redirect/index.html (meta refresh + JS location.replace + rel=canonical + noindex)
• Add redirect/404.html (identical content for deep-link catch)
• Move CNAME from public/ to redirect/
• Simplify .github/workflows/deploy.yml — no Astro build
• Astro source (src/, package.json, astro.config.ts) left in place for git history; prune in a follow-up

Test plan

• Confirm https://danielmiller.ca/ resolves (verified live)
• Merge → verify GitHub Actions "Deploy redirect to GitHub Pages" workflow succeeds
• curl -I https://www.millerdatabases.com/ → expect 200 with meta refresh
• Hit an old post URL (e.g. https://www.millerdatabases.com/the-copilot-delusion/) → expect 404.html served, redirect fires
• Check GitHub repo Settings > Pages: source must be "GitHub Actions" (not "Deploy from branch")

Follow-ups

• Archive repo when DNS confirmed
• Delete src/, package.json, astro.config.ts, ghost-export.json in cleanup commit
• Cancel millerdatabases.com renewal when done