fix(ai_client): restore get_current_tier() backward-compat for patchers

src/ai_client.py

@@ -162,6 +162,10 @@ def get_current_tier_result() -> Result[str]:
  """Returns the current tier from thread-local storage as a Result."""
  return Result(data=getattr(_local_storage, "current_tier", None))
 
+def get_current_tier() -> str | None:
+ """Backward-compat wrapper; prefer get_current_tier_result().data."""
+ return get_current_tier_result().data
+
 def set_current_tier(tier: Optional[str]) -> None:
  """Sets the current tier in thread-local storage."""
  _local_storage.current_tier = tier

src/app_controller.py

@@ -4233,7 +4233,7 @@ class AppController:
   """
   session_logger.log_tool_call(script, result, None)
   session_logger.log_tool_output(result)
-  source_tier = ai_client.get_current_tier_result().data
+  source_tier = ai_client.get_current_tier()
   with self._pending_tool_calls_lock:
    self._pending_tool_calls.append({"script": script, "result": result, "ts": time.time(), "source_tier": source_tier})