fix(landing): https + correct subdomains, drop dead CA-cert step

The guest landing page advertised http:// service URLs (mixed-content on the
https origin) and the wrong packwiz subdomain:
- authUrl / authlibUrl: http -> https
- packwizUrl: http://packwiz. -> https://pack.  (correct vhost)
- serverAddress: mc. -> apex (connect to ${BASE_DOMAIN}:25565)
- remove caCertUrl + the "trust the local CA" join step (airgap-only, /ca.crt
  no longer exists) and its en/es/eu i18n strings + type.

Also fix the stale http BaseURL example in plan/03-drasl.md.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

landing/src/pages/[...lang].astro

@@ -207,9 +207,6 @@ const dustBits = Array.from({ length: 16 }, (_, i) => {
                 <p>
                   {t.join.s2.registerPre} <a href={site.authUrl}>{site.authUrl}</a>.
                 </p>
-                <span class="hint">
-                  {t.join.s2.caPre} <a href={site.caCertUrl}>{t.join.s2.caLink}</a> {t.join.s2.caPost}
-                </span>
               </div>
             </div>