Add nav/footer, contact form, privacy/terms drafts, first course landing page

- baseof.html: proper header/nav/footer, CSS custom properties for
  light/dark, button and form component styles — no external theme
  dependency, avoiding the submodule/version churn from the earlier
  PaperMod attempt.
- Contact page: real form (honeypot spam protection) posting to the eec
  service's new /contact endpoint, replacing the plain mailto CTA.
- Privacy Policy and Terms drafts — grounded in what's actually true here
  (self-hosted mail/course infra, no third-party trackers), flagged as
  drafts pending review.
- courses/ section with a generic single template driven by front matter
  (eec_slug, pitch) and the first course, Find Your Right Readers —
  landing page only; the actual course content isn't authored in
  eec-courses yet, so enrolling will 404 until that's written.
- Fixed hugo.toml baseURL (was www.reground.org, but Caddy's canonical
  host is the bare domain — www redirects to it, not the other way).

content/courses/_index.md

@@ -0,0 +1,6 @@
+---
+title: "Courses"
+description: "Free email courses from ReGround."
+---
+
+Short, free email courses — sign up and they land in your inbox at whatever pace suits you.