fix(deploy): ramiel's own names redirected to HTTPS by hand behind HAProxy (ADR 0039)

With https_port 8443, Caddy's automatic HTTP-to-HTTPS redirects would send
visitors of code.halkyon.app, halkyon.app and learn.halkyon.app to :8443,
which is closed from outside. A site of their own on http:// redirects them
to the default port instead. The README's step for home's key points at the
host's step 5, and checks that 8443 stays closed and the redirect carries no
port.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Signed-off-by: Tizian 「ティツィアーン」 <raisondetredev@pm.me>

test/deploy/halkyon_li_forward_test.dart

@@ -87,6 +87,24 @@ void main() {
       expect(caddy, contains('redir https://{host}{uri} 308'));
       expect(caddy, isNot(contains('reverse_proxy')));
     });
+
+    test("redirects its own names to HTTPS by hand, so Caddy's automatic "
+        'redirects never point at 8443', () {
+      expect(
+        caddy,
+        contains(
+          'http://code.halkyon.app, http://halkyon.app, '
+          'http://learn.halkyon.app {',
+        ),
+      );
+      expect(
+        RegExp(
+          r'^\s*redir (\S+)',
+          multiLine: true,
+        ).allMatches(caddy).map((match) => match[1]),
+        everyElement('https://{host}{uri}'),
+      );
+    });
   });
 
   group("ramiel's end of the tunnel (D8, D9)", () {