chore: initial project import

backend/src/Monitor.Backend.Application/BackendOptions.cs

@@ -0,0 +1,62 @@
+namespace Monitor.Backend.Application;
+
+/// <summary>Backend 的可调参数（保留期等也可以通过 settings 改，这里是默认值与硬上限）。</summary>
+public sealed class BackendOptions
+{
+    /// <summary>数据目录：<c>monitor.db</c> 与 <c>raw/</c>。</summary>
+    public string DataDirectory { get; set; } = "data";
+
+    /// <summary>面板的对外地址（用于生成安装命令）。</summary>
+    public string? PublicUrl { get; set; }
+
+    public int Pbkdf2Iterations { get; set; } = 600_000;
+
+    /// <summary>会话 Cookie 带 Secure 标记（只提供 HTTPS）。本机用 HTTP 调试时才关闭。</summary>
+    public bool SecureCookies { get; set; } = true;
+
+    /// <summary>
+    /// 允许跨域调用 API 的前端来源，逗号分隔（如 <c>http://localhost:5173,https://panel.example.com</c>，或 <c>*</c>）；空 = 不允许，只有同源。
+    /// 跨域只支持 Bearer 令牌（不带 Cookie），所以不影响会话的安全。
+    /// </summary>
+    public string? CorsOrigins { get; set; }
+
+    public TimeSpan SessionLifetime { get; set; } = TimeSpan.FromHours(12);
+
+    public int LoginAttemptsPerMinute { get; set; } = 10;
+
+    public int RawRetentionDays { get; set; } = 30;
+
+    public int TestRawRetentionDays { get; set; } = 90;
+
+    public int Metric10sRetentionHours { get; set; } = 48;
+
+    public int Metric1mRetentionDays { get; set; } = 30;
+
+    public int Metric5mRetentionDays { get; set; } = 365;
+
+    public int EventRetentionDays { get; set; } = 365;
+
+    public int HostRetentionDays { get; set; } = 7;
+
+    /// <summary>分钟窗口在结束之后再等一会儿，让迟到的块先到。</summary>
+    public TimeSpan WindowGrace { get; set; } = TimeSpan.FromSeconds(60);
+
+    public TimeSpan AnalysisPollInterval { get; set; } = TimeSpan.FromSeconds(5);
+
+    public TimeSpan QueryTimeout { get; set; } = TimeSpan.FromSeconds(10);
+
+    public int MaxSsePerClient { get; set; } = 4;
+
+    public int MaxSseTopics { get; set; } = 32;
+
+    public int MaxPointsPerSeries { get; set; } = 2000;
+
+    public int MaxMetricsPerQuery { get; set; } = 32;
+
+    public int MaxCompareAgents { get; set; } = 20;
+
+    /// <summary>初始管理员（只在没有任何用户时创建）。</summary>
+    public string? InitialAdminUser { get; set; }
+
+    public string? InitialAdminPassword { get; set; }
+}