Keep EmbeddedArchive probe open to prevent AWAIT_PUBLICATION_CONNECTED race

The WaitForArchiveReady probe was disposed immediately after confirming the
archive was up. On Windows CI this created a race: between REMOVE_PUBLICATION
(from the probe) and the test's own ADD_PUBLICATION, the archive briefly had no
subscriber on its control channel and stopped sending Status Messages. The new
publication would then timeout after 10s at AWAIT_PUBLICATION_CONNECTED.

Fix: store the probe AeronArchive as a field and keep it alive for the full
lifetime of the EmbeddedArchive instance. The probe is disposed in Dispose()
after the JVM is killed (where it's safe and fast since OwnsAeronClient=false),
and in KillProcess() before killing so pub/sub are cleanly removed first.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: strangelydim

src/Adaptive.Archiver.IntegrationTests/Infrastructure/EmbeddedArchive.cs

@@ -49,6 +49,7 @@ internal sealed class EmbeddedArchive : IDisposable
 
         private readonly Process _archive;
         private readonly string _archiveDir;
+        private AeronArchive _probeClient;
 
         public bool PreserveArchiveDirOnDispose { get; set; }
 
@@ -153,6 +154,11 @@ public AeronArchive.Context CreateClientContext(string aeronDirectoryName) =>
         /// </summary>
         public void KillProcess()
         {
+            // Dispose the probe before killing the JVM so its pub/sub are cleanly removed
+            // from the conductor before the process disappears under them.
+            try { _probeClient?.Dispose(); } catch { }
+            _probeClient = null;
+
             ShutdownProcess(_archive, "EmbeddedArchive");
 
             try
@@ -172,6 +178,11 @@ public void Dispose()
         {
             ShutdownProcess(_archive, "EmbeddedArchive");
 
+            // Dispose the probe after the JVM is dead so there is no window between
+            // REMOVE_PUBLICATION and a subsequent ADD_PUBLICATION to the same channel.
+            try { _probeClient?.Dispose(); } catch { }
+            _probeClient = null;
+
             bool exited = false;
             try { exited = _archive.HasExited; } catch { }
 
@@ -251,7 +262,11 @@ private void WaitForArchiveReady(string aeronDirectoryName, AeronClient aeronCli
                     {
                         ctx.AeronClient(aeronClient);
                     }
-                    using var client = AeronArchive.Connect(ctx);
+                    // Keep the probe open for the lifetime of this EmbeddedArchive instance.
+                    // Disposing it immediately creates a window between REMOVE_PUBLICATION and
+                    // the test's own ADD_PUBLICATION where the archive sees no subscriber and
+                    // won't send Status Messages, causing AWAIT_PUBLICATION_CONNECTED timeouts.
+                    _probeClient = AeronArchive.Connect(ctx);
                     return;
                 }
                 catch (Exception e)