Add prod nginx image with clearnet, onion, and SPA build.

Multi-stage frontend embed, envsubst entrypoint for TLS vhosts and upload body limits, shared locations with minimal response headers and zero access logs.

nginx/conf.d/clearnet.conf.template

@@ -0,0 +1,28 @@
+server {
+    listen 80;
+    server_name ${CLEARNET_DOMAIN} www.${CLEARNET_DOMAIN};
+
+    access_log off;
+
+    location /.well-known/acme-challenge/ {
+        root /var/www/certbot;
+    }
+
+    location / {
+        return 301 https://$host$request_uri;
+    }
+}
+
+server {
+    listen 443 ssl;
+    server_name ${CLEARNET_DOMAIN} www.${CLEARNET_DOMAIN};
+
+    access_log off;
+
+    ssl_certificate /etc/nginx/certs/live/${CLEARNET_DOMAIN}/fullchain.pem;
+    ssl_certificate_key /etc/nginx/certs/live/${CLEARNET_DOMAIN}/privkey.pem;
+
+    ${ONION_LOCATION_HEADER}
+
+    include /etc/nginx/snippets/private-image-locations.conf;
+}

nginx/conf.d/onion.conf.template

@@ -0,0 +1,8 @@
+server {
+    listen 8080;
+    server_name _;
+
+    access_log off;
+
+    include /etc/nginx/snippets/private-image-locations.conf;
+}