docs(agents): 添加AI代理行为准则文档

- 定义了环境能力清单和工具选择规则
- 规定了XML文档注释、内联注释和架构级注释要求
- 明确了代码风格包括命名规范、格式化和C#约定
- 设立了测试覆盖范围、组织结构和验证命令标准
- 制定了安全输入验证、依赖管理和权限控制规则
- 确立了文档更新、任务跟踪和审查完成标准
- 更新了浮点数比较算法中的容差计算方式
- 优化了数值精度验证逻辑以避免十进制步进误差

AGENTS.md

@@ -104,6 +104,10 @@ All generated or modified code MUST include clear and meaningful comments where
 - Keep `using` directives at the top of the file and sort them consistently.
 - Separate logical blocks with blank lines when it improves readability.
 - Prefer one primary type per file unless the surrounding project already uses a different local pattern.
+- Unless there is a clear and documented reason to keep a file large, keep a single source file under roughly 800-1000
+  lines.
+- If a file grows beyond that range, contributors MUST stop and check whether responsibilities should be split before
+  continuing; treating oversized files as the default is considered a design smell.
 - Keep line length readable. Around 120 characters is the preferred upper bound.
 
 ### C# Conventions

GFramework.Game/Config/YamlConfigSchemaValidator.cs

@@ -1745,8 +1745,9 @@ internal static class YamlConfigSchemaValidator
 
     /// <summary>
     ///     判断数值是否满足 <c>multipleOf</c>。
-    ///     双精度浮点比较会保留一个与商值量级相关的微小容差，
-    ///     以避免运行时与 JS 工具侧在 0.1 / 0.01 这类十进制步进上出现伪失败。
+    ///     双精度浮点比较会保留一个与步进量级相关的微小容差，
+    ///     以避免运行时与 JS 工具侧在 0.1 / 0.01 这类十进制步进上出现伪失败，
+    ///     同时避免值越大就无限放宽合法余数范围。
     /// </summary>
     /// <param name="value">当前值。</param>
     /// <param name="divisor">步进约束。</param>
@@ -1755,8 +1756,8 @@ internal static class YamlConfigSchemaValidator
     {
         var quotient = value / divisor;
         var nearestInteger = Math.Round(quotient);
-        var tolerance = 1e-9 * Math.Max(1d, Math.Abs(quotient));
-        return Math.Abs(quotient - nearestInteger) <= tolerance;
+        var tolerance = 1e-9 * Math.Max(1d, Math.Abs(divisor));
+        return Math.Abs(value - (nearestInteger * divisor)) <= tolerance;
     }
 
     /// <summary>