ZeroDb 增加自定义异常，方便在外部捕获

Extensions/FreeSql.Extensions.ZeroEntity/Models/SchemaValidationException.cs

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+using System;
+
+namespace FreeSql.Extensions.ZeroEntity.Models
+{
+    public class SchemaValidationException : Exception
+    {
+        public SchemaValidationException(string message) : base(message) { }
+    }
+}

Extensions/FreeSql.Extensions.ZeroEntity/Models/SchemaValidationResult.cs

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+using System;
+using System.Collections.Generic;
+using System.Text;
+
+namespace FreeSql.Extensions.ZeroEntity.Models
+{
+    public class SchemaValidationResult
+    {
+        public readonly static SchemaValidationResult _schemaValidationResult = new SchemaValidationResult();
+
+        public static SchemaValidationResult SuccessedResult => _schemaValidationResult;
+
+        public SchemaValidationResult(string errorMessage)
+        {
+            ErrorMessage = errorMessage;
+        }
+
+        public string ErrorMessage { get; set; }
+        public bool Succeeded { get; set; } = false;
+    }
+}