add dbgate and mssql

docs/domains.md

@@ -145,6 +145,38 @@ Active
 
 ---
 
+### DbGate
+
+Domain:
+
+```text
+dbgate.silveressence.net
+```
+
+Purpose:
+
+* HTTPS database administration portal
+
+Container:
+
+```text
+dbgate
+```
+
+Routing:
+
+```text
+Nginx Proxy Manager -> dbgate:3000
+```
+
+Status:
+
+```text
+Active
+```
+
+---
+
 ## DNS
 
 DNS records should point to: