HAKAN'S REQUIREMENT - Refactor API base URL configuration structure

Replaced ApiBaseUrl and DataApiBaseUrl with BaseUrl, ApiDefaultUrl, and service-specific configuration sections (AuthService, UserManagerService, DbFirstService). Updated AppSettings and all code references to use the new structure. Revised logic for HTTP client base URL selection to prefer service-specific settings. Updated appsettings files and added an example configuration for clarity and maintainability.

DbFirst.BlazorWebApp/appsettings.Example.json

@@ -0,0 +1,19 @@
+{
+  "ApiDefaultUrl": "https://localhost:7204/",
+  "AuthService": {
+    "BaseUrl": "http://172.24.12.39:9090/",
+    "Login": "/api/Auth/db-first/login",
+    "Logout": "auth/logout",
+    "Check": "auth/check"
+  },
+  "UserManagerService": {
+    "BaseUrl": null,
+    "GetUserInfo": "user/info",
+    "UpdateUserInfo": "user/update"
+  },
+  "DbFirstService": {
+    "BaseUrl": "https://localhost:7204/",
+    "GetData": "dbfirst/data",
+    "UpdateData": "dbfirst/update"
+  }
+}