Python SDK 0.14.4

Fixed

• Use core 0.3.9 so a worker returns a failure response when a Python BaseException escapes an executor. Previously the native core logged the error and dropped the response, leaving the invocation waiting for its lease to expire.
• Preserve empty-string answers when resuming human input. Reject unsupported trigger filters, input mappings, batching and delays during workflow registration instead of allowing the runtime to skip them.
• Apply function retry policies inside workflow steps.
• Resolve output references in client results, add asynchronous output and result-waiting helpers, and return output values from chat helpers.
• Surface classification judge failures instead of returning a zero score, and recover missing classification labels when the response contains a supported label.
• Restrict direct agent and tool dispatch to explicitly listed worker components.

Security

• Breaking: serverless invokes now require a non-empty signing secret. A
  missing secret returns HTTP 503 (WORKERLESS_SIGNING_SECRET_REQUIRED) before
  executing user code. For local development, explicitly set allow_unsigned=True;
  this logs a startup warning and permits unsigned invokes only when no secret
  resolves. Configured secrets are still verified. The manifest remains public.