Preserve recovery transcripts and add user-approved agent requests

Append successful offline recovery with a duplicate-warning marker and retain failed replay sources. Offer newly available microphones through confirmation notifications.

Add project discovery metadata and blocking association approval, plus nonblocking workflow requests that start a separate settings-agent conversation. Include regression tests, OpenSpec changes, and verified local Release startup.

MeetingAssistant/Recording/NaudioCaptureSource.cs

@@ -4,11 +4,12 @@ using NAudio.Wave;
 
 namespace MeetingAssistant.Recording;
 
-internal sealed class NaudioCaptureAudioSource : IMeetingAudioSource
+internal sealed class NaudioCaptureAudioSource : IMeetingAudioSource, IDisposable
 {
     private readonly IWaveIn capture;
     private readonly string sourceName;
     private readonly ILogger logger;
+    private int disposed;
 
     public NaudioCaptureAudioSource(
         IWaveIn capture,
@@ -22,13 +23,15 @@ internal sealed class NaudioCaptureAudioSource : IMeetingAudioSource
 
     public IAsyncEnumerable<AudioChunk> CaptureAsync(CancellationToken cancellationToken)
     {
-        return CaptureWith(capture, sourceName, logger, cancellationToken);
+        return CaptureWith(cancellationToken);
     }
 
-    private static async IAsyncEnumerable<AudioChunk> CaptureWith(
-        IWaveIn capture,
-        string sourceName,
-        ILogger logger,
+    public void Dispose()
+    {
+        if (Interlocked.Exchange(ref disposed, 1) == 0) capture.Dispose();
+    }
+
+    private async IAsyncEnumerable<AudioChunk> CaptureWith(
         [System.Runtime.CompilerServices.EnumeratorCancellation] CancellationToken cancellationToken)
     {
         var channel = Channel.CreateUnbounded<AudioChunk>();
@@ -83,7 +86,7 @@ internal sealed class NaudioCaptureAudioSource : IMeetingAudioSource
         }
         finally
         {
-            capture.Dispose();
+            Dispose();
         }
     }
 }