v2.4.3

Fixes two task queue issues: pydantic secret params were masked when a task
run was serialized to the queue, and a params validation error on the
consumer side crashed the worker.

• Secret params now survive the round-trip through the task queue and the
  cpu-bound subprocess. Task runs are serialized for the queue with secret
  values revealed via the new params_dump helper; all other dumps (logs,
  endpoints) keep secrets masked.
  (#103)
• A task run consumed from the queue with invalid params no longer kills the
  consumer worker. The broker raises the new TaskParamsError carrying the
  task run, and the consumer logs the error and marks the run as failed.
  (#103)