Add basic caddy role

roles/caddy/templates/etc/caddy/Caddyfile.j2

@@ -0,0 +1,29 @@
+# Global options
+{
+    email {{ caddy_email }}
+}
+
+# Common security response headers
+(security-headers) {
+    header {
+        # disable Google FLoC tracking
+        Permissions-Policy interest-cohort=()
+
+        # enable HSTS
+        Strict-Transport-Security max-age=31536000
+
+        # disable clients from sniffing the media type
+        X-Content-Type-Options nosniff
+
+        # clickjacking protection: refuse to allow rendering this page
+        # in a frame, iframe, etc.
+        X-Frame-Options DENY
+
+        # keep referrer data off of HTTP connections
+        Referrer-Policy no-referrer-when-downgrade
+    }
+}
+
+# Import additional caddy config files in /etc/caddy/conf.d/
+# Note: these are imported in lexical sort order!
+import /etc/caddy/conf.d/*