Fix Caddy sites directory path (sites, not site)

The target server uses /etc/caddy/sites/ (plural) for per-site
config files, not /etc/caddy/site/.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

ansible/deploy.yml

@@ -7,7 +7,7 @@
 #     and the playbook is invoked from inside ansible/.
 #   - Caddy is already installed on the server with the
 #     caddy-dns/cloudflare plugin and loads per-site files from
-#     /etc/caddy/site/*.conf.
+#     /etc/caddy/sites/*.conf.
 #   - The user running `ansible-playbook` has passwordless sudo.
 #
 # Usage:
@@ -102,9 +102,9 @@
     # ---------------------------------------------------------
     # Caddy vhost for auth.e-cosplay.fr
     # ---------------------------------------------------------
-    - name: Ensure /etc/caddy/site directory exists
+    - name: Ensure /etc/caddy/sites directory exists
       ansible.builtin.file:
-        path: /etc/caddy/site
+        path: /etc/caddy/sites
         state: directory
         mode: "0755"
         owner: root

ansible/group_vars/all.yml

@@ -6,8 +6,8 @@ auth_domain: auth.e-cosplay.fr
 keycloak_local_port: 9450
 
 # Caddy (assumed already installed with the caddy-dns/cloudflare plugin
-# and configured to load per-site files from /etc/caddy/site/*.conf)
-caddy_site_file: /etc/caddy/site/e-auth.conf
+# and configured to load per-site files from /etc/caddy/sites/*.conf)
+caddy_site_file: /etc/caddy/sites/e-auth.conf
 
 # Cloudflare API token consumed by the caddy-dns/cloudflare plugin
 # for the ACME DNS-01 challenge.