fix: preserve transcription failures and audio diagnostics

meetingnotes/ProcessTap/ProcessTap.swift

@@ -63,6 +63,10 @@ final class ProcessTap {
     @ObservationIgnored
     private(set) var tapStreamDescription: AudioStreamBasicDescription?
     @ObservationIgnored
+    private(set) var tapAdvertisedStreamDescription: AudioStreamBasicDescription?
+    @ObservationIgnored
+    private(set) var aggregateInputStreamDescription: AudioStreamBasicDescription?
+    @ObservationIgnored
     private var invalidationHandler: InvalidationHandler?
 
     @ObservationIgnored
@@ -249,6 +253,7 @@ final class ProcessTap {
         do {
             logger.debug("Attempting to read audio tap stream basic description for tapID #\(tapID)...")
             let advertisedDescription = try tapID.readAudioTapStreamBasicDescription()
+            self.tapAdvertisedStreamDescription = advertisedDescription
 
             // The aggregate device may adapt the tap to the active hardware's
             // sample rate. Its input stream is the format actually delivered
@@ -256,7 +261,9 @@ final class ProcessTap {
             // advertisement. Using the latter can halve the written duration
             // when, for example, a 48 kHz tap is delivered at 24 kHz.
             do {
-                self.tapStreamDescription = try aggregateDeviceID.readInputStreamBasicDescription()
+                let aggregateDescription = try aggregateDeviceID.readInputStreamBasicDescription()
+                self.aggregateInputStreamDescription = aggregateDescription
+                self.tapStreamDescription = aggregateDescription
                 logger.info("Using aggregate input stream description: \(String(describing: self.tapStreamDescription), privacy: .public); tap advertised: \(String(describing: advertisedDescription), privacy: .public)")
             } catch {
                 self.tapStreamDescription = advertisedDescription