fix(nginx): make Let's Encrypt opt-in per service

certbot cannot issue for internal hostnames (*.nas.local), which made
nginx-enabled services with internal names fail on deploy.

Add a <service>_nginx_letsencrypt flag (default false) and computed
<service>_nginx_ssl_certificate/_key paths: when off the vhost uses the
shared self-signed cert (nginx_default_ssl_cert), when on it uses the
Let's Encrypt lineage. Gate the certbot include on the flag and apply the
pattern to all service roles (deluge, fdroid, gitea, grafana, immich,
metabase, ntfy, prowlarr, radarr, seerr, static_web, uptime_kuma).

roles/gitea/defaults/main.yml

@@ -31,3 +31,16 @@ gitea_disable_registration: false
 # Nginx reverse proxy configuration
 gitea_nginx_enabled: true
 gitea_nginx_hostname: "{{ gitea_domain }}"
+# Let's Encrypt (certbot) requires a publicly-resolvable hostname. Internal
+# names (e.g. *.nas.local) cannot get a public cert: leave this false to use
+# the shared self-signed cert (nginx_default_ssl_cert). Set true once a public
+# DNS record points at the host.
+gitea_nginx_letsencrypt: false
+gitea_nginx_ssl_certificate: >-
+  {{ gitea_nginx_letsencrypt | ternary(
+     '/etc/letsencrypt/live/' ~ gitea_nginx_hostname ~ '/fullchain.pem',
+     nginx_default_ssl_cert) }}
+gitea_nginx_ssl_certificate_key: >-
+  {{ gitea_nginx_letsencrypt | ternary(
+     '/etc/letsencrypt/live/' ~ gitea_nginx_hostname ~ '/privkey.pem',
+     nginx_default_ssl_key) }}