[DMINQ]

Description

Accept reusable destination objects in broker methods while preserving
existing string arguments.

Redis:

• PubSub in publish and request.
• ListSub in publish, request, and publish_batch.
• StreamSub in publish and request.
• Inherit StreamSub.maxlen when maxlen is None; explicit values,
  including 0, take precedence.

NATS:

• Accept JStream in NatsBroker.publish and NatsBroker.request.
• Normalize it to its name before producer selection and middleware execution.
• Keep the target subject as a separate argument.

Sending does not modify the supplied objects. Includes updated typing,
tests, and documentation.

Fixes #3305.

Type of change

• New feature (a non-breaking change that adds functionality)
• Documentation update

Validation

• 19 tests passed against real Redis and NATS, covering request/reply,
  publishing, PubAck, batch publishing, and Redis pipelines.
• 205 tests passed without broker connections, including documentation examples.
• Ruff formatting and lint checks passed.
• Mypy, Pyright, and Pyrefly passed.
• Documentation built successfully; 152 pages checked.