Route social crawlers on invoice URLs to Open Graph HTML.

Bots hitting /invoices/:id on manage get API OG markup; browsers still load the SPA.

Co-authored-by: Cursor <cursoragent@cursor.com>

deploy/nginx-dashboards-ssl.conf

@@ -1,4 +1,12 @@
 # HTTPS dashboards (Certbot SANs on meshkee-dashboards)
+#
+# Link-preview bots (WhatsApp, etc.) hitting /invoices/:id get Open Graph HTML
+# from the API; browsers still receive the SPA.
+
+map $http_user_agent $meshkee_link_preview_bot {
+    default 0;
+    ~*(whatsapp|facebookexternalhit|facebot|twitterbot|linkedinbot|slackbot|telegrambot|discordbot) 1;
+}
 
 server {
     listen 443 ssl;
@@ -7,6 +15,24 @@ server {
     ssl_certificate_key /etc/letsencrypt/live/meshkee-dashboards/privkey.pem;
     ssl_protocols TLSv1.2 TLSv1.3;
 
+    location ~ ^/invoices/(?<invoice_public_id>[0-9]{6,32})$ {
+        if ($meshkee_link_preview_bot = 1) {
+            rewrite ^ /__internal/invoice-og/$invoice_public_id last;
+        }
+        root /var/www/meshkee/super-admin;
+        try_files /index.html =404;
+    }
+
+    location ~ ^/__internal/invoice-og/([0-9]{6,32})$ {
+        internal;
+        proxy_pass https://api.meshkee.com/api/v1/public/invoices/$1/og;
+        proxy_ssl_server_name on;
+        proxy_set_header Host api.meshkee.com;
+        proxy_set_header X-Real-IP $remote_addr;
+        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
+        proxy_set_header X-Forwarded-Proto $scheme;
+    }
+
     location / {
         root /var/www/meshkee/super-admin;
         try_files $uri $uri/ /index.html;