Refactor AppConfig and update configuration settings across environments. Changed properties to use set accessors, added AllowedOrigins, and improved error handling in Program.cs. Updated appsettings files for development, production, and added new structure for user data retrieval.

backend-dotnet/appsettings.Production.json

@@ -14,7 +14,17 @@
       "Microsoft.AspNetCore": "Warning"
     }
   },
-  "AllowedHosts": "*"
+  "AllowedHosts": "*",
+  "AppConfig": {
+    "DbHost": "postgres",
+    "DbPort": "5432",
+    "DbName": "dexdemo",
+    "DbUser": "dexdemo",
+    "DbPassword": "dexdemo",
+    "Issuer": "https://dex.127.0.0.1.sslip.io/",
+    "InsecureDevMode": false,
+    "AllowedOrigins": ["https://yourdomain.com"]
+  }
 }