Replace InvalidOperationException with custom config exception

Refactored DbModelOptions and EntityBaseOptions to throw DbModelConfigurationException instead of InvalidOperationException for configuration errors. Added necessary using directives for the new exception type to improve error clarity and specificity.

src/ReC.Infrastructure/Options/DbModelOptions.cs

@@ -1,4 +1,5 @@
-using ReC.Infrastructure.Options.Shared;
+using ReC.Infrastructure.Exceptions;
+using ReC.Infrastructure.Options.Shared;
 
 namespace ReC.Infrastructure.Options;
 
@@ -18,6 +19,6 @@ public record DbModelOptions
         if(cluster.TryGetValue(nameof(T), out var entityOptions))
             entityOptions.EnsureProperties<T>();
         else
-            throw new InvalidOperationException($"Entity options for type '{typeof(T).FullName}' not found.");
+            throw new DbModelConfigurationException($"Entity options for type '{typeof(T).FullName}' not found.");
     }
 }