fix(dictate): finish Muse on final transcript

services/dictate/src/pi_dictate_service/backend.py

@@ -422,8 +422,11 @@ class QueuedCloudTurn:
                         self._provider_event_bytes -= size
                     raise ProviderError(self._provider_prefix + "_event_overflow", "provider event queue is full") from error
         except ProviderError as error:
+            # Preserve a provider failure that races with successful
+            # finalization. Cancellation does not consume this error, but it
+            # avoids recursively closing a transport we are already closing.
+            self._receiver_error = error
             if not self._cancel_event.is_set():
-                self._receiver_error = error
                 self._abort_transport()
         except Exception:
             if not self._cancel_event.is_set():

services/dictate/src/pi_dictate_service/backends/meta.py

@@ -177,13 +177,10 @@ class MetaTurn(QueuedCloudTurn):
 
     def _finish_provider(self) -> str:
         deadline = time.monotonic() + self._timeout
-        transcript: str | None = None
         while time.monotonic() < deadline:
             event = self._next_provider_event(max(0.01, deadline - time.monotonic()))
             if event is None:
-                if transcript is None:
-                    raise ProviderError("meta_premature_close", "Meta closed without a final transcript")
-                return transcript
+                raise ProviderError("meta_premature_close", "Meta closed without a final transcript")
             _validate_meta_event(event)
             event_type = event["type"]
             if event_type == "error":
@@ -198,11 +195,9 @@ class MetaTurn(QueuedCloudTurn):
             if isinstance(value, Mapping):
                 value = value.get("text")
             try:
-                transcript = bounded_provider_text(value)
+                return bounded_provider_text(value)
             except ProviderError as error:
                 raise ProviderError("meta_malformed_event", "Meta sent an invalid transcript") from error
-            # Keep reading until the provider's normal close.  A subsequent
-            # error or abnormal close therefore cannot be mistaken for success.
         raise ProviderError("meta_timeout", "timed out waiting for Meta final transcript")