Scenario conditions in dialogs: option if= hides choices, when moved here from stat checks; command schemas

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

tests/WhenCommandStrategyTests.cs

@@ -0,0 +1,42 @@
+namespace Cthangover.Mods.Dialog.Tests
+{
+    using Cthangover.Core.Mods.Testing;
+    using Cthangover.Core.Scenes;
+    using Cthangover.Mods.Dialog.Scenarios;
+
+    /// <summary><c>when</c> jumps on the shared condition language, evaluated when the line runs.</summary>
+    public class WhenCommandStrategyTests
+    {
+        private static string Outcome(string scenario)
+        {
+            var dlg = ScenarioParser.Parse(scenario);
+            var runtime = new DialogRuntime();
+            runtime.SetDialogQueueAndRun(null, dlg.Queue, null);
+            runtime.Run();
+            return runtime.GetVariable("outcome");
+        }
+
+        [ModTest("when/true_false_and_else")]
+        static void TrueFalseAndElse(ModTestContext ctx)
+        {
+            ModAssert.Equal("yes", Outcome("when true -> :yes\nset outcome no\nend\n:yes\nset outcome yes\nend\n"), "true jumps");
+            ModAssert.Equal("no", Outcome("when false -> :yes\nset outcome no\nend\n:yes\nset outcome yes\nend\n"), "false falls through");
+            ModAssert.Equal("other", Outcome("when false -> :yes else=other\nset outcome no\nend\n:yes\nset outcome yes\nend\n:other\nset outcome other\nend\n"), "false takes else");
+        }
+
+        [ModTest("when/reads_state_when_the_line_runs")]
+        static void ReadsStateWhenTheLineRuns(ModTestContext ctx)
+        {
+            ScenarioCondition.SetFlag("test_when_flag", "0");
+            try
+            {
+                const string scenario = "flag test_when_flag 2\nwhen \"test_when_flag >= 2 && !false\" -> :yes\nset outcome no\nend\n:yes\nset outcome yes\nend\n";
+                ModAssert.Equal("yes", Outcome(scenario), "a flag set two lines earlier counts");
+            }
+            finally
+            {
+                ScenarioCondition.SetFlag("test_when_flag", "0");
+            }
+        }
+    }
+}