Lilith (Version 3)

using System.Xml.Linq;​namespace Lilith.Agent.ScenarioSystem;​internal sealed record ScenarioXml(    string Id,    string Title,    bool RunOnBoot,    IReadOnlyList<ScenarioStepXml> Steps);​internal abstract record ScenarioStepXml(string Kind);​/// <summary>Chat step — same idea as TestManager &lt;Step&gt; prompts.</summary>internal sealed record ChatStepXml(string Prompt, string? ExpectContains, string? ExpectEquals) : ScenarioStepXml("chat");​internal static class ScenarioXmlParser{    public static ScenarioXml Parse(string xml)    {        var doc = XDocument.Parse(xml);        var root = doc.Root ?? throw new InvalidOperationException("Scenario XML missing root element.");        if (!string.Equals(root.Name.LocalName, "Scenario", StringComparison.OrdinalIgnoreCase))            throw new InvalidOperationException("Scenario XML root must be <Scenario>.");​        string id = root.Attribute("id")?.Value?.Trim() ?? "";        string title = root.Attribute("title")?.Value?.Trim() ?? id;        bool runOnBoot = string.Equals(root.Attribute("run_on")?.Value, "boot", StringComparison.OrdinalIgnoreCase);​        if (string.IsNullOrWhiteSpace(id))            throw new InvalidOperationException("<Scenario> requires id attribute.");​        var steps = new List<ScenarioStepXml>();        foreach (var el in root.Elements())        {            if (!el.Name.LocalName.Equals("Step", StringComparison.OrdinalIgnoreCase))                throw new InvalidOperationException($"Scenario XML only supports <Step> elements (found <{el.Name}>).");​            string prompt = el.Value.Trim();            if (string.IsNullOrWhiteSpace(prompt))                throw new InvalidOperationException("<Step> must not be empty.");​            steps.Add(new ChatStepXml(                prompt,                el.Attribute("expect_contains")?.Value?.Trim(),                el.Attribute("expect_equals")?.Value?.Trim()));        }​        if (steps.Count == 0)            throw new InvalidOperationException("Scenario has no steps.");​        return new ScenarioXml(id, title, runOnBoot, steps);    }}​