fix(asr): keep recordings when streaming recognition fails or stalls

- Keep recording after a streaming ASR error and retry the captured PCM
  through batch ASR before reporting a failure.
- Treat an expired ASR wait as a stall so batch fallback still runs.
- Prime the managed Volcengine stream on mic touch and adopt it only while
  fresh and open.
- Auto-scroll the live transcript to the newest recognized text.

OSGKeyboardHostSupport/Services/CloudASR/ManagedVolcengineASRClient.swift

@@ -765,6 +765,12 @@ private final class ManagedVolcengineASRSession: CloudASRStreamingSession, @unch
         }
     }
 
+    var acceptsAudio: Bool {
+        lock.withLock { state in
+            !state.cancelled && state.failure == nil && !state.receiveClosed && !state.endSent
+        }
+    }
+
     func cancel() {
         let changed = lock.withLock { state -> Bool in
             guard !state.cancelled else { return false }