fix(launcher): close Campaign LA LA1 review findings

tests/AcDream.Runtime.Tests/Session/SessionStatusWriterTests.cs

@@ -97,6 +97,63 @@ public sealed class SessionStatusWriterTests
         writer.Started("s1");
     }
 
+    /// <summary>
+    /// F3: both hosts share this writer but have separate reconnect command
+    /// adapters. The sink therefore closes an open connection before it
+    /// accepts another connected edge, preserving a coherent external
+    /// lifecycle even if a host has no reconnect-specific status hook.
+    /// </summary>
+    [Fact]
+    public void SecondConnectedEdgeFirstClosesTheRetiringConnection()
+    {
+        using TemporaryFile file = TemporaryFile.Create();
+        var writer = new SessionStatusWriter(file.Path);
+
+        writer.Connected("s1");
+        writer.Connected("s1");
+
+        JsonElement[] events = File.ReadAllLines(file.Path)
+            .Select(Parse)
+            .ToArray();
+        Assert.Equal(
+            ["connected", "disconnected", "connected"],
+            events.Select(static item => item.GetProperty("e").GetString()));
+        Assert.Equal(
+            "reconnect",
+            events[1].GetProperty("reason").GetString());
+    }
+
+    /// <summary>
+    /// F6: exited is a terminal fact, not an append request. Repeated host
+    /// disposal and any late callback after disposal must not create a second
+    /// terminal edge or resurrect the stream. If a host exits while still
+    /// connected, the writer closes that connection first with a distinct,
+    /// truthful reason.
+    /// </summary>
+    [Fact]
+    public void ExitedIsIdempotentTerminalAndClosesAnOpenConnection()
+    {
+        using TemporaryFile file = TemporaryFile.Create();
+        var writer = new SessionStatusWriter(file.Path);
+
+        writer.Connected("s1");
+        writer.Exited("s1", 0, "graceful");
+        writer.Exited("s1", 1, "duplicate-must-not-win");
+        writer.Connected("s1");
+
+        JsonElement[] events = File.ReadAllLines(file.Path)
+            .Select(Parse)
+            .ToArray();
+        Assert.Equal(
+            ["connected", "disconnected", "exited"],
+            events.Select(static item => item.GetProperty("e").GetString()));
+        Assert.Equal(
+            "process-exit",
+            events[1].GetProperty("reason").GetString());
+        Assert.Equal(0, events[2].GetProperty("code").GetInt32());
+        Assert.Equal("graceful", events[2].GetProperty("reason").GetString());
+    }
+
     /// <summary>
     /// F7 (Campaign LA LA1 review fix round): replaces the earlier
     /// "DoesNotContain 'hunter2'/'password'" assertion, which could never