feat(client): add task hub name filter to orchestration queries

[Hardik K (hardikkaurani)]

Resolves #222.

Summary

The protobuf InstanceQuery message defines field 4 taskHubNames (repeated google.protobuf.StringValue). While instance_id_prefix was previously added to OrchestrationQuery, filtering orchestration queries by task hub names was still missing.

This change adds task_hub_names to OrchestrationQuery and serializes it in build_query_instances_req() to align with client query capabilities across SDKs.

Changes

1. durabletask/client.py:

   • Added task_hub_names: list[str] | None = None to OrchestrationQuery.
   • Backward compatibility and existing parameter order are fully preserved.

2. durabletask/internal/client_helpers.py:

   • In build_query_instances_req(), serialized task_hub_names into InstanceQuery.taskHubNames as wrappers_pb2.StringValue.

3. tests/durabletask/test_batch_actions.py:

   • Added test_orchestration_query_serializes_task_hub_names to verify taskHubNames protobuf serialization.
   • Added test_orchestration_query_serializes_task_hub_names_and_instance_id_prefix covering combined filter queries.
   • Updated test_orchestration_query_preserves_positional_argument_order to verify default behavior when fields are omitted.

4. CHANGELOG.md:

   • Documented OrchestrationQuery.task_hub_names under Unreleased.

Validation

• Unit tests for query filter serialization pass cleanly.
• Strict Pyright type check passes with 0 errors.
• Default query behavior remains fully backward-compatible.

[Hardik K (hardikkaurani)]

Hello Bernd Verst (@berndverst),

I have submitted this pull request to resolve issue #222 by adding task_hub_names to OrchestrationQuery and serializing it through build_query_instances_req via wrappers_pb2.StringValue.

Positional argument order and backward compatibility for existing query instances are maintained, unit test coverage has been added in tests/durabletask/test_batch_actions.py, and strict Pyright type checking passes with zero errors.

Please review when convenient and let me know if any adjustments are desired.

[Copilot]

🟢 Approval recommended

The additive change preserves compatibility, matches the protobuf contract, and includes focused regression coverage.

No open issues 🎉

What changed in this PR

Adds task hub filtering to orchestration queries, completing the remaining filter support requested in #222 while preserving existing constructor argument order.

Changes:

• Adds task_hub_names and serializes it into the existing protobuf field.
• Tests task hub filtering alone and alongside instance ID prefixes.
• Documents the new capability under Unreleased.

File	Description
tests/​durabletask/​test_batch_actions.py	Adds serialization and compatibility assertions.
durabletask/​internal/​client_helpers.py	Serializes task hub names into query requests.
durabletask/​client.py	Adds the optional task hub filter.
CHANGELOG.md	Documents the new query capability.

_{Review effort: Balanced}